NEET Physics

Mechanics

A particle is moving in a circular path of radius r with a constant speed v. The work done by the centripetal force in one complete revolution is4
a) Zero
b) 2πmv^2
c) 4πmv^2
d) πmv^2ns= 0

Ans: 0

The key points are:

The particle is moving in a circular path with constant speed v.
The centripetal force is always directed towards the center of the circular path and is perpendicular to the direction of motion.
When the work done by a force is calculated using the formula W = F·d·cos(θ), where θ is the angle between the force and the displacement, the angle between the centripetal force and the displacement (arc length) is always 90 degrees.
The cosine of 90 degrees is 0, so the work done by the centripetal force is zero.

Therefore, the work done by the centripetal force in one complete revolution is zero.1

As explained in the search results:”Since there is a circular motion, and no displacement is caused by the force, the work done is said to be zero. Hence, the given statement is true.”3“The centripetal force is always perpendicular to the direction of motion. Only the component of the force in the direction of motion can do work. The centripetal force has no such component, so it can never do work.”5

“The centripetal force is always directed into the centre of the circle that is the path for the object. Even though the object is constantly changing direction, the motion at any instant is always tangential to the circle. This gives us the situation where the angle, θ, between the force and the direction of motion is 90°. If we apply this to our equation for work: W = F·d·cos(θ), we conclude that no work is being done on an object in uniform circular motion.”2Therefore, the work done by the centripetal force in one complete revolution is zero

A block of mass m is placed on a rough horizontal surface. The coefficient of friction between the block and the surface is μ. If the block is given an initial velocity v0, the distance traveled by the block before coming to rest is
a) v0^2 / 2μg
b) v0^2 / μg
c) v0^2 / 4μg
d) v0^2 / 3μg

Ans: v0^2 / (2μg)

Based on the information provided in the search results, the correct answer to the question “A block of mass m is placed on a rough horizontal surface. The coefficient of friction between the block and the surface is μ. If the block is given an initial velocity v0, the distance traveled by the block before coming to rest is” is:a) v0^2 / 2μg

Explanation:The search results, specifically1, 2, 3, and4, provide the following information:When a block of mass m is placed on a rough horizontal surface with a coefficient of friction μ, and the block is given an initial velocity v0, the distance traveled by the block before coming to rest is given by the formula:x = v0^2 / 2μg

Where:

x is the distance traveled by the block
v0 is the initial velocity of the block
μ is the coefficient of friction between the block and the surface
g is the acceleration due to gravity

This formula is derived in the search results, particularly in4, which shows the step-by-step derivation. The other options (b, c, d) are incorrect, as they do not match the formula provided in the search results for the distance traveled by the block before coming to rest.

A particle is moving in a circular path of radius r with a constant speed v. The centripetal acceleration of the particle is1 2 4
a) v^2 / r
b) v / r
c) 2πv / r
d) 2πv^2 / r

Ans a_c = v^2/r”

Based on the information provided in the search results, the correct answer to the question “A particle is moving in a circular path of radius r with a constant speed v. The centripetal acceleration of the particle is” is:a) v^2 / rExplanation:The search results clearly state that the formula for the centripetal acceleration of a particle moving in a circular path with constant speed v and radius r is:a_c = v^2 / rThis is derived in the search results, specifically in1

and2, which provide the following explanations:From1:
“Substituting this into our expression for a_c yields
a_c = v^2/r”From2:
“The centripetal acceleration a has a magnitude equal to the square of the body’s speed c v along the curve divided by the distance r from the centre of the circle to the moving body; that is, a = c v 2/ r.”The other options (b, c, d) are incorrect, as they do not match the formula for centripetal acceleration derived in the search results.

A body of mass m is suspended by a massless string. If the body is set into oscillation, the period of oscillation is1 2 4
a) 2π√(m/g)
b) 2π√(l/g)
c) 2π√(l/mg)
d) 2π√(m/l)

Ans T = 2π/ω = 2π√(l/g)

To determine the period of oscillation for a body of mass m suspended by a massless string, we can use the formula for the period of a simple pendulum:T = 2π√(l/g)

Where:

T is the period of oscillation
l is the length of the string
g is the acceleration due to gravity

The derivation of this formula is as follows:

Derivation of the Period Formula

The restoring force for a simple pendulum is provided by the force of gravity acting on the suspended mass.
The equation of motion for the angular displacement θ of the pendulum is:
m * l * d²θ/dt² = -m * g * sin(θ)
For small angles (θ << 1), we can approximate sin(θ) ≈ θ, so the equation becomes:
m * l * d²θ/dt² = -m * g * θ
This is the equation of motion for a simple harmonic oscillator, with a natural frequency ω = √(g/l).
The period of oscillation is the inverse of the natural frequency:
T = 2π/ω = 2π√(l/g)

Therefore, the correct answer is option b) 2π√(l/g).The other options are not correct because they do not accurately represent the period of oscillation for a body suspended by a massless string.

The work done by the centripetal force in one complete revolution of a particle moving in a circular path of radius r with a constant speed v is:
Based on the search results provided, the work done by the centripetal force in one complete revolution of a particle moving in a circular path of radius r with a constant speed v is zero.The key points are:

In uniform circular motion, the centripetal force is always directed towards the center of the circular path and is perpendicular to the velocity of the particle. 1 2 3
Since the centripetal force is perpendicular to the velocity, the work done by the centripetal force is zero. The work done by a force is the dot product of the force and the displacement, and since the force and displacement are perpendicular, the work is zero. 1 2 3

Therefore, the work done by the centripetal force in one complete revolution of a particle moving in a circular path of radius r with a constant speed v is zero. 1 2 3

Electrostatics

The work done in bringing two point charges q1 and q2 placed at a distance r apart from infinity is1 2 4 5
a) q1q2/4πε0r
b) q1q2/2πε0r
c) q1q2/πε0r
d) 2q1q2/πε0r

The correct answer is a) q1q2/4πε0r.

Explanation:According to the search results provided, the potential energy of a system of two point charges q1 and q2 placed at a distance r apart is given by the expression:

U = q1q2/4πε0r

This is because the work done in bringing the two charges from infinity to a distance r apart is equal to the change in potential energy of the system.The key points are:

The potential energy of the system is zero when the two charges are infinitely far apart.
When the charges are brought to a finite distance r, the potential energy of the system becomes q1q2/4πε0r.
This change in potential energy is equal to the work done in bringing the charges from infinity to the distance r.

As stated in the search results:”The change in electric potential energy is given by ⇒ ΔU = Vq Where V is the potential at second charge due to the first charge and q is the second charge. The potential due to a single charge system is given by ⇒ V = q/4πε0r. The change in potential energy for a two charge system can be defined as ⇒ ΔU = Vq = (q1/4πε0r)q2.”

The energy stored in a parallel plate capacitor with a potential difference V between its plates is1 2 4 5
a) CV^2/2
b) CV^2
c) 2CV^2
d) CV^2/4

The correct answer is a) CV^2/2.

The energy stored in a parallel plate capacitor with a potential difference V between its plates is given by the formula:U = CV^2/2

Where:

U is the energy stored in the capacitor
C is the capacitance of the capacitor
V is the potential difference between the plates

This formula is derived by considering the work done in charging the capacitor. As charge is added to the capacitor, the potential difference increases linearly. The total work done, which is equal to the energy stored, is the integral of the potential difference times the incremental charge, which results in the expression CV^2/2.

The other options are incorrect:

b) CV^2 is twice the correct formula
c) 2CV^2 is four times the correct formula
d) CV^2/4 is half the correct formula

The electric potential at a point on the surface of a spherical shell of radius R with a point charge q at its center is5
a) kq/R
b) kq/R^2
c) kq/2R
d) kq/4πR

The correct answer is d) kq/4πR.

The electric potential at a point on the surface of a spherical shell of radius R with a point charge q at its center is given by the formula:V = kq/4πR

Where:

k is the Coulomb constant (8.99 × 10^9 N⋅m^2/C^2)
q is the point charge at the center of the shell
R is the radius of the spherical shell

This can be derived from the general expression for the electric potential due to a point charge:V = kq/rWhere r is the distance from the point charge.Since the point is on the surface of the spherical shell, the distance r is equal to the radius R of the shell.Therefore, the electric potential at a point on the surface of the spherical shell is V = kq/R. Dividing this by 4πR gives the final expression of V = kq/4πR.

A point charge q is placed at the center of a spherical shell of radius R. The electric potential at a point on the surface of the shell is
a) kq/R
b) kq/R^2
c) kq/2R
d) kq/4πR

The correct answer is

c) kq/2R.

Explanation:The electric potential due to a point charge q at a distance r from the charge is given by the equation:V = kq/rWhere k is the Coulomb constant (k = 9 x 10^9 N⋅m^2/C^2).In this case, the point charge q is placed at the center of a spherical shell of radius R. The electric potential at a point on the surface of the shell is the potential due to the point charge q at a distance R from the charge.Substituting r = R in the equation, we get:V = kq/

RTherefore, the correct answer is c) kq/2R.The other options are incorrect:a) kq/R is the electric potential at the surface of the shell, not the potential at a point on the surface.
b) kq/R^2 is the electric field at the surface of the shell, not the electric potential.
d) kq/4πR is the electric potential energy of the point charge q, not the electric potential.

The electric potential at a point on the surface of a spherical shell of radius R with a point charge q at its center is:
Answer: a) kq/R
Explanation: The electric potential at a point on the surface of a spherical shell with a point charge q at its center is given by the formula: V = kq/R, where k is the Coulomb constant and R is the radius of the shell.

Optics

1. The fringe width in a Young’s double-slit experiment with slit separation d and screen-slit distance D is1 2 4 5
  a) λD/d (Ans)
  b) λd/D
  c) λ/d
  d) λD/2d
2. The power of a combination of a convex lens of focal length f and a concave lens of focal length -f placed in contact is1 2 4 5
  a) 0
  b) 1/f
  c) 2/f
  d) -1/f
3. The magnifying power of a compound microscope with an objective lens of focal length f1 and an eyepiece of focal length f2 is1 2 4 5
  a) f2/f1
  b) f1/f2
  c) (f1+f2)/f1f2
  d) (f1+f2)/f1
4. The fringe width in a Young’s double-slit experiment with slit separation d and screen-slit distance D is:
  Answer: a) λD/d
  Explanation: The fringe width in a Young’s double-slit experiment is given by the formula: Δy = λD/d, where λ is the wavelength of the light, D is the distance between the screen and the slits, and d is the separation between the slits.
5. The power of a combination of a convex lens of focal length f and a concave lens of focal length -f placed in contact is:
  Answer: a) 0
  Explanation: When a convex lens of focal length f and a concave lens of focal length -f are placed in contact, the power of the combination is zero, as the positive power of the convex lens is canceled out by the negative power of the concave lens.
6. The magnifying power of a compound microscope with an objective lens of focal length f1 and an eyepiece of focal length f2 is:
  Answer: a) f2/f1
  Explanation: The magnifying power of a compound microscope is given by the formula: M = f2/f1, where f1 is the focal length of the objective lens and f2 is the focal length of the eyepiece.

The fringe width in a Young’s double-slit experiment with slit separation d and screen-slit distance D is:
Answer: a) λD/d
Explanation: The fringe width in a Young’s double-slit experiment is given by the formula: Δy = λD/d, where λ is the wavelength of the light, D is the distance between the screen and the slits, and d is the separation between the slits.
The power of a combination of a convex lens of focal length f and a concave lens of focal length -f placed in contact is:
Answer: a) 0
Explanation: When a convex lens of focal length f and a concave lens of focal length -f are placed in contact, the power of the combination is zero, as the positive power of the convex lens is canceled out by the negative power of the concave lens.
The magnifying power of a compound microscope with an objective lens of focal length f1 and an eyepiece of focal length f2 is:
Answer: a) f2/f1
Explanation: The magnifying power of a compound microscope is given by the formula: M = f2/f1, where f1 is the focal length of the objective lens and f2 is the focal length of the eyepiece.
The fringe width in a Young’s double-slit experiment with slit separation d and screen-slit distance D is:
a) λD/d
b) λd/D
c) λ/d
d) λD/2dAnswer: a) λD/d
Explanation: The fringe width in a Young’s double-slit experiment is given by the formula: Δy = λD/d, where λ is the wavelength of the light, D is the distance between the screen and the slits, and d is the separation between the slits.
The power of a combination of a convex lens of focal length f and a concave lens of focal length -f placed in contact is:
a) 0
b) 1/f
c) 2/f
d) -1/fAnswer: a) 0
Explanation: When a convex lens of focal length f and a concave lens of focal length -f are placed in contact, the power of the combination is zero, as the positive power of the convex lens is canceled out by the negative power of the concave lens.

12)The magnifying power of a compound microscope with an objective lens of focal length f1 and an eyepiece of focal length f2 is:
a) f2/f1
b) f1/f2
c) (f1+f2)/f1f2
d) (f1+f2)/f1 Answer: a) f2/f1
Explanation: The magnifying power of a compound microscope is given by the formula: M = f2/f1, where f1 is the focal length of the objective lens and f2 is the focal length of the eyepiece

The fringe width in a Young’s double-slit experiment with slit separation d and screen-slit distance D is
a) λD/d
b) λd/D
c) λ/d
d) λD/2d
The power of a combination of a convex lens of focal length f and a concave lens of focal length -f placed in contact is1 2 4 5
a) 0
b) 1/f
c) 2/f
d) -1/f
The magnifying power of a compound microscope with an objective lens of focal length f1 and an eyepiece of focal length f2 is1 2 4 5
a) f2/f1
b) f1/f2
c) (f1+f2)/f1f2
d) (f1+f2)/f1
In a Young’s double-slit experiment, the distance between the slits is d and the distance between the screen and the slits is D. The fringe width is1 2 4 5
a) λD/d
b) λd/D
c) λ/d
d) λD/2d
A convex lens of focal length f is placed in contact with a concave lens of focal length -f. The power of the combination is1 2 4 5
a) 0
b) 1/f
c) 2/f
d) -1/f
In a compound microscope, the objective lens has a focal length f1, and the eyepiece has a focal length f2. The magnifying power of the microscope is1 2 4 5
a) f2/f1
b) f1/f2
c) (f1+f2)/f1f2
d) (f1+f2)/f1

Modern Physics

The de Broglie wavelength of an electron accelerated through a potential difference V is1 2 4 5
a) h/√(2meV)
b) h/√(meV)
c) h/√(meV/2)
d) h/√(2meV/h^2)
The energy of a photon is hf, where h is Planck’s constant and f is the frequency of the photon. The momentum of the photon is1 2 4 5
a) hf/c
b) h/λ
c) hf/λ
d) h/f
The radioactive decay law is given by N = N0e^(-λt), where N is the number of radioactive nuclei at time t, N0 is the initial number of radioactive nuclei, and λ is the decay constant. The half-life of the radioactive substance is1 2 4 5
a) ln(2)/λ
b) 1/λ
c) 2/λ
d) ln(2)/2λ
The de Broglie wavelength of an electron accelerated through a potential difference V is1 2 4 5
a) h/√(2meV)
b) h/√(meV)
c) h/√(meV/2)
d) h/√(2meV/h^2)
The momentum of a photon with energy hf is1 2 4 5
a) hf/c
b) h/λ
c) hf/λ
d) h/f
The half-life of a radioactive substance with a decay constant λ is1 2 4 5
a) ln(2)/λ
b) 1/λ
c) 2/λ
d) ln(2)/2λ
In a series RLC circuit, the current lags the voltage by an angle θ. The value of tan(θ) is1 2 4 5
a) ωL/R
b) R/ωL
c) ωC/R
d) R/ωC
The equivalent resistance of a wire of resistance R cut into n equal parts and connected in parallel is1 2 4 5
a) R/n
b) nR
c) R/n^2
d) n^2R
The potential difference between the ends of a potentiometer wire connected to a cell of emf E and internal resistance r is1 2 4 5
a) E
b) E/(1+r/R)
c) E/(1+R/r)
d) E/(1+R/2r)
The de Broglie wavelength of an electron accelerated through a potential difference V is:
a) h/√(2meV)
b) h/√(meV)
c) h/√(meV/2)
d) h/√(2meV/h^2)Answer: a) h/√(2meV)
Explanation: The de Broglie wavelength of an electron accelerated through a potential difference V is given by the formula: λ = h/√(2meV), where h is the Planck constant, m is the mass of the electron, and e is the charge of the electron.
The momentum of a photon with energy hf is:
a) hf/c
b) h/λ
c) hf/λ
d) h/fAnswer: c) hf/λ
Explanation: The momentum of a photon is given by the formula: p = h/λ, where h is the Planck constant and λ is the wavelength of the photon. Since the energy of the photon is hf, the momentum can be expressed as p = hf/λ.
The half-life of a radioactive substance with a decay constant λ is:
a) ln(2)/λ
b) 1/λ
c) 2/λ
d) ln(2)/2λAnswer: a) ln(2)/λ
Explanation: The half-life of a radioactive substance is the time it takes for the number of radioactive nuclei to decrease to half of its initial value. The half-life is given by the formula: t1/2 = ln(2)/λ, where λ is the decay constant of the radioactive substance.

Thermodynamics

The work done by a system in an isothermal process is1 2 4 5
a) Zero
b) PΔV
c) -PΔV
d) nRΔT
The efficiency of a Carnot engine operating between two reservoirs at temperatures T1 and T2 (T1 > T2) is1 2 4 5
a) 1 – T2/T1
b) T1/T2
c) T2/T1
d) 1 – T1/T2
The mean free path of a gas molecule is inversely proportional to1 2 4 5
a) The square root of the pressure
b) The pressure
c) The square of the pressure
d) The cube of the pressure
The work done in the isothermal expansion of an ideal gas from volume V1 to volume V2 is1 2 4 5
a) nRT ln(V2/V1)
b) -nRT ln(V2/V1)
c) nRT(V2-V1)
d) -nRT(V2-V1)

In an isothermal process, the work done by the system is1 2 4 5
a) Zero
b) PΔV
c) -PΔV
d) nRΔT
The efficiency of a Carnot engine operating between two reservoirs at temperatures T1 and T2 (T1 > T2) is1 2 4 5
a) 1 – T2/T1
b) T1/T2
c) T2/T1
d) 1 – T1/T2
The mean free path of a gas molecule in a container is inversely proportional to1 2 4 5
a) The square root of the pressure
b) The pressure
c) The square of the pressure
d) The cube of the pressure
The work done in isothermal expansion of an ideal gas from volume V1 to volume V2 is1 2 4 5
a) nRT ln(V2/V1)
b) -nRT ln(V2/V1)
c) nRT(V2-V1)
d) -nRT(V2-V1)

The work done by a system in an isothermal process is:
a) Zero
b) PΔV
c) -PΔV
d) nRΔTAnswer: c) -PΔV
Explanation: In an isothermal process, the work done by the system is given by the formula: W = -PΔV, where P is the pressure and ΔV is the change in volume.
The efficiency of a Carnot engine operating between two reservoirs at temperatures T1 and T2 (T1 > T2) is:
a) 1 – T2/T1
b) T1/T2
c) T2/T1
d) 1 – T1/T2Answer: a) 1 – T2/T1
Explanation: The efficiency of a Carnot engine operating between two reservoirs at temperatures T1 and T2 (T1 > T2) is given by the formula: η = 1 – T2/T1, where T1 is the temperature of the hot reservoir and T2 is the temperature of the cold reservoir.
The mean free path of a gas molecule is inversely proportional to:
a) The square root of the pressure
b) The pressure
c) The square of the pressure
d) The cube of the pressureAnswer: b) The pressure
Explanation: The mean free path of a gas molecule is inversely proportional to the pressure of the gas, as the higher the pressure, the more collisions the gas molecules will experience, resulting in a shorter mean free path.
The work done in the isothermal expansion of an ideal gas from volume V1 to volume V2 is:
a) nRT ln(V2/V1)
b) -nRT ln(V2/V1)
c) nRT(V2-V1)
d) -nRT(V2-V1)Answer: a) nRT ln(V2/V1)
Explanation: The work done in the isothermal expansion of an ideal gas from volume V1 to volume V2 is given by the formula: W = nRT ln(V2/V1), where n is the number of moles of the gas, R is the universal gas constant, and T is the absolute temperature.

Waves and Oscillations

The time period of a simple pendulum is proportional to
a) √(l/g)
b) √(g/l)
c) l/√g
d) √(l*g)
The speed of a transverse wave on a string is given by
a) √(T/μ)
b) √(μ/T)
c) √(T*μ)
d) √(μ/ρ)
The fundamental frequency of a closed organ pipe is
a) v/4L
b) v/2L
c) v/L
d) 2v/L
The quality factor (Q) of an oscillating system is defined as
a) ω/Δω
b) Δω/ω
c) ω^2/Δω
d) Δω^2/ω^2

Gravitation

The gravitational potential energy of a particle of mass m at a distance r from the center of a spherical mass M is
a) -GMm/r
b) -Gm/r^2
c) -GMm/r^2
d) -Gm/r
The escape velocity of a particle from the surface of a planet of mass M and radius R is
a) √(2GM/R)
b) √(GM/R)
c) √(GM/R^2)
d) √(2G/R)
The time period of a satellite in a circular orbit around the Earth is
a) 2π√(r^3/GM)
b) 2π√(r/GM)
c) 2π√(r^2/GM)
d) 2π√(GM/r)
The gravitational force between two masses M1 and M2 separated by a distance r is
a) G(M1+M2)/r^2
b) GM1M2/r^2
c) G(M1-M2)/r^2
d) GM1M2/r

Atomic Physics

The radius of the nth Bohr orbit of a hydrogen atom is proportional to
a) n^2
b) n
c) 1/n^2
d) 1/n
The energy of an electron in the nth Bohr orbit of a hydrogen atom is proportional to
a) -1/n^2
b) -1/n
c) n^2
d) n
The angular momentum of an electron in the nth Bohr orbit of a hydrogen atom is proportional to
a) n
b) n^2
c) √n
d) 1/n
The wavelength of the Lyman series of the hydrogen atom is given by the Rydberg formula as
a) 1/[1/1^2 – 1/n^2]
b) 1/[1/2^2 – 1/n^2]
c) 1/[1/3^2 – 1/n^2]
d) 1/[1/4^2 – 1/n^2]

Nuclear Physics

The binding energy per nucleon of a nucleus is given by the formula
a) BE/A = a – b(A-2Z)^2/A
b) BE/A = a + b(A-2Z)^2/A
c) BE/A = a – b(A-2Z)^2/A^2
d) BE/A = a + b(A-2Z)^2/A^2
The half-life of a radioactive substance is the time in which
a) Half the nuclei decay
b) One-fourth the nuclei decay
c) Three-fourths the nuclei decay
d) One-eighth the nuclei decay
The activity of a radioactive substance is proportional to
a) The number of radioactive nuclei
b) The square of the number of radioactive nuclei
c) The square root of the number of radioactive nuclei
d) The logarithm of the number of radioactive nuclei
The energy released in a nuclear fission reaction is primarily due to the
a) Conversion of mass to energy
b) Repulsive force between the protons
c) Attractive force between the nucleons
d) Kinetic energy of the fission fragments

Semiconductor Electronics

The energy band gap of a semiconductor is
a) The energy difference between the conduction band and the valence band
b) The energy difference between the Fermi level and the conduction band
c) The energy difference between the Fermi level and the valence band
d) The energy difference between the highest occupied energy level and the lowest unoccupied energy level
The majority charge carriers in an n-type semiconductor are
a) Electrons
b) Holes
c) Both electrons and holes
d) Neither electrons nor holes
The forward bias current in a p-n junction diode is primarily due to the
a) Drift of majority charge carriers
b) Drift of minority charge carriers
c) Diffusion of majority charge carriers
d) Diffusion of minority charge carriers
The output voltage of a common emitter amplifier is
a) In phase with the input voltage
b) Out of phase with the input voltage
c) Proportional to the input voltage
d) Independent of the input voltage

Electromagnetic Induction

The induced emf in a coil of N turns and area A, placed in a time-varying magnetic field B, is given by
a) -NAΔB/Δt
b) -NΔB/ΔA
c) -NΔA/ΔB
d) -NΔB/Δt
The self-inductance of a solenoid of length l, cross-sectional area A, and number of turns N is proportional to
a) N^2/l
b) N^2/A
c) N^2/l^2
d) N^2/A^2
The mutual inductance between two coils is proportional to
a) The number of turns in each coil
b) The square of the number of turns in each coil
c) The distance between the coils
d) The inverse of the distance between the coils
The eddy currents induced in a conducting material are
a) Proportional to the rate of change of the magnetic field
b) Inversely proportional to the rate of change of the magnetic field
c) Proportional to the square of the rate of change of the magnetic field
d) Inversely proportional to the square of the rate of change of the magnetic field

Dual Nature of Matter and Radiation

The de Broglie wavelength of a particle with momentum p is
a) h/p
b) p/h
c) h^2/p
d) p^2/h
The photoelectric effect is characterized by
a) The emission of electrons from a metal surface when exposed to light
b) The emission of photons from a metal surface when exposed to light
c) The absorption of light by a metal surface
d) The reflection of light from a metal surface
The energy of a photon is given by the formula
a) E = hf
b) E = h/f
c) E = h^2/f
d) E = f/h
The Compton effect is the
a) Increase in the wavelength of a photon after it interacts with a free electron
b) Decrease in the wavelength of a photon after it interacts with a free electron
c) Increase in the energy of a photon after it interacts with a free electron
d) Decrease in the energy of a photon after it interacts with a free electron

Waves and Oscillations

The time period of a simple pendulum is proportional to
a) √(l/g)
b) √(g/l)
c) l/√g
d) √(l*g)
The speed of a transverse wave on a string is given by
a) v = √(T/μ)
b) v = √(μ/T)
c) v = √(T*μ)
d) v = √(μ/ρ)
The fundamental frequency of a closed organ pipe is
a) f = v/4L
b) f = v/2L
c) f = v/L
d) f = 2v/L
The quality factor (Q) of an oscillating system is defined as
a) Q = ω/Δω
b) Q = Δω/ω
c) Q = ω^2/Δω
d) Q = Δω^2/ω^2
The time period of a simple pendulum is proportional to:
Answer: a) √(l/g)
Explanation: The time period (T) of a simple pendulum is given by the formula T = 2π√(l/g), where l is the length of the pendulum and g is the acceleration due to gravity. Therefore, the time period is proportional to √(l/g).
The speed of a transverse wave on a string is given by:
Answer: a) √(T/μ)
Explanation: The speed (v) of a transverse wave on a string is given by the formula v = √(T/μ), where T is the tension in the string and μ is the mass per unit length of the string.
The fundamental frequency of a closed organ pipe is:
Answer: a) v/4L
Explanation: The fundamental frequency (f) of a closed organ pipe is given by the formula f = v/4L, where v is the speed of sound in the medium and L is the length of the pipe.
The quality factor (Q) of an oscillating system is defined as:
Answer: a) ω/Δω
Explanation: The quality factor (Q) of an oscillating system is defined as the ratio of the angular frequency (ω) to the bandwidth (Δω) of the system.

Gravitation

The gravitational potential energy of a particle of mass m at a distance r from the center of a spherical mass M is
a) U = -GMm/r
b) U = -Gm/r^2
c) U = -GMm/r^2
d) U = -Gm
The gravitational potential energy of a particle of mass m at a distance r from the center of a spherical mass M is:
Answer: a) -GMm/r
Explanation: The gravitational potential energy (U) of a particle of mass m at a distance r from the center of a spherical mass M is given by the formula U = -GMm/r, where G is the gravitational constant.
The escape velocity of a particle from the surface of a planet of mass M and radius R is:
Answer: a) √(2GM/R)
Explanation: The escape velocity (v_e) of a particle from the surface of a planet of mass M and radius R is given by the formula v_e = √(2GM/R), where G is the gravitational constant.
The time period of a satellite in a circular orbit around the Earth is:
Answer: a) 2π√(r^3/GM)
Explanation: The time period (T) of a satellite in a circular orbit around the Earth is given by the formula T = 2π√(r^3/GM), where r is the radius of the orbit and M is the mass of the Earth.
The gravitational force between two masses M1 and M2 separated by a distance r is:
Answer: b) GM1M2/r^2
Explanation: The gravitational force (F) between two masses M1 and M2 separated by a distance r is given by the formula F = GM1M2/r^2, where G is the gravitational constant.

Atomic Physics

The radius of the nth Bohr orbit of a hydrogen atom is proportional to:
Answer: d) 1/n
Explanation: The radius (r_n) of the nth Bohr orbit of a hydrogen atom is proportional to 1/n, where n is the principal quantum number.
The energy of an electron in the nth Bohr orbit of a hydrogen atom is proportional to:
Answer: a) -1/n^2
Explanation: The energy (E_n) of an electron in the nth Bohr orbit of a hydrogen atom is proportional to -1/n^2, where n is the principal quantum number.
The angular momentum of an electron in the nth Bohr orbit of a hydrogen atom is proportional to:
Answer: a) n
Explanation: The angular momentum (L) of an electron in the nth Bohr orbit of a hydrogen atom is proportional to n, where n is the principal quantum number.
The wavelength of the Lyman series of the hydrogen atom is given by the Rydberg formula as:
Answer: a) 1/[1/1^2 – 1/n^2]
Explanation: The wavelength (λ) of the Lyman series of the hydrogen atom is given by the Rydberg formula λ = 1/[1/1^2 – 1/n^2], where n is the principal quantum number.

Nuclear Physics

The binding energy per nucleon of a nucleus is given by the formula:
Answer: a) BE/A = a – b(A-2Z)^2/A
Explanation: The binding energy per nucleon (BE/A) of a nucleus is given by the formula BE/A = a – b(A-2Z)^2/A, where A is the mass number, Z is the atomic number, and a and b are constants.
The half-life of a radioactive substance is the time in which:
Answer: a) Half the nuclei decay
Explanation: The half-life of a radioactive substance is the time it takes for half the radioactive nuclei to decay.
The activity of a radioactive substance is proportional to:
Answer: a) The number of radioactive nuclei
Explanation: The activity (A) of a radioactive substance is proportional to the number of radioactive nuclei present.
The energy released in a nuclear fission reaction is primarily due to the:
Answer: a) Conversion of mass to energy
Explanation: The energy released in a nuclear fission reaction is primarily due to the conversion of a small amount of mass into a large amount of energy, as described by Einstein’s famous equation E = mc^2.

Semiconductor Electronics

The energy band gap of a semiconductor is:
Answer: a) The energy difference between the conduction band and the valence band
Explanation: The energy band gap of a semiconductor is the energy difference between the conduction band and the valence band, which determines the electrical and optical properties of the material.
The majority charge carriers in an n-type semiconductor are:
Answer: a) Electrons
Explanation: In an n-type semiconductor, the majority charge carriers are electrons, which are introduced by doping the semiconductor with impurities that have a surplus of electrons.
The forward bias current in a p-n junction diode is primarily due to the:
Answer: c) Diffusion of majority charge carriers
Explanation: In a forward-biased p-n junction diode, the current is primarily due to the diffusion of majority charge carriers (electrons in the n-type region and holes in the p-type region) across the junction.
The output voltage of a common emitter amplifier is:
Answer: b) Out of phase with the input voltage
Explanation: In a common emitter amplifier, the output voltage is 180 degrees out of phase with the input voltage, meaning that the output voltage is inverted compared to the input voltage.

Electromagnetic Induction

The induced emf in a coil of N turns and area A, placed in a time-varying magnetic field B, is given by:
Answer: a) -NAΔB/Δt
Explanation: The induced emf (ε) in a coil of N turns and area A, placed in a time-varying magnetic field B, is given by Faraday’s law of electromagnetic induction: ε = -NAΔB/Δt, where ΔB is the change in the magnetic field over time Δt.
The self-inductance of a solenoid of length l, cross-sectional area A, and number of turns N is proportional to:
Answer: a) N^2/l
Explanation: The self-inductance (L) of a solenoid is proportional to the square of the number of turns (N^2) divided by the length of the solenoid (l).
The mutual inductance between two coils is proportional to:
Answer: a) The number of turns in each coil
Explanation: The mutual inductance (M) between two coils is proportional to the number of turns (N) in each coil, as the induced emf in one coil is due to the changing magnetic field produced by the current in the other coil.
The eddy currents induced in a conducting material are:
Answer: a) Proportional to the rate of change of the magnetic field
Explanation: Eddy currents induced in a conducting material are proportional to the rate of change of the magnetic field, as described by Faraday’s law of electromagnetic induction.

Dual Nature of Matter and Radiation

The de Broglie wavelength of a particle with momentum p is:
Answer: a) h/p
Explanation: The de Broglie wavelength (λ) of a particle with momentum p is given by the formula λ = h/p, where h is the Planck constant.
The photoelectric effect is characterized by:
Answer: a) The emission of electrons from a metal surface when exposed to light
Explanation: The photoelectric effect is the emission of electrons from a metal surface when it is exposed to light, as the energy of the photons is transferred to the electrons in the metal.
The energy of a photon is given by the formula:
Answer: a) E = hf
Explanation: The energy (E) of a photon is given by the formula E = hf, where h is the Planck constant and f is the frequency of the photon.
The Compton effect is the:
Answer: a) Increase in the wavelength of a photon after it interacts with a free electron
Explanation: The Compton effect is the increase in the wavelength of a photon after it interacts with a free electron, as the photon transfers some of its energy and momentum to the electron.

Magnetic Effects of Current and Magnetism

The magnetic field inside a long, straight current-carrying wire is:
Answer: a) Proportional to the current and inversely proportional to the distance from the wire
Explanation: The magnetic field (B) inside a long, straight current-carrying wire is proportional to the current (I) and inversely proportional to the distance (r) from the wire, as described by Ampère’s law.
The magnetic moment of a current loop of area A and current I is:
Answer: a) IA
Explanation: The magnetic moment (μ) of a current loop of area A and current I is given by the formula μ = IA, where I is the current and A is the area of the loop.
The force between two parallel current-carrying wires is:
Answer: a) Proportional to the product of the currents and inversely proportional to the distance between the wires
Explanation: The force (F) between two parallel current-carrying wires is proportional to the product of the currents (I1 and I2) and inversely proportional to the distance (d) between the wires, as described by Ampère’s law.
The magnetic susceptibility of a diamagnetic material is:
Answer: b) Negative
Explanation: The magnetic susceptibility of a diamagnetic material is negative, meaning that the material is slightly repelled by an external magnetic field.
The magnetic field inside a long, straight current-carrying wire is
a) Proportional to the current and inversely proportional to the distance from the wire
b) Proportional to the current and the distance from the wire
c) Inversely proportional to the current and the distance from the wire
d) Inversely proportional to the current and proportional to the distance from the wire
The magnetic moment of a current loop of area A and current I is
a) IA
b) I/A
c) IA^2
d) I/A^2
The force between two parallel current-carrying wires is
a) Proportional to the product of the currents and inversely proportional to the distance between the wires
b) Proportional to the product of the currents and the distance between the wires
c) Inversely proportional to the product of the currents and the distance between the wires
d) Inversely proportional to the product of the currents and proportional to the distance between the wires
The magnetic susceptibility of a diamagnetic material is
a) Positive
b) Negative
c) Zero
d) Infinity

The magnetic field inside a long, straight current-carrying wire is:
Answer: a) Proportional to the current and inversely proportional to the distance from the wire
Explanation: The magnetic field (B) inside a long, straight current-carrying wire is proportional to the current (I) and inversely proportional to the distance (r) from the wire, as described by Ampère’s law.
The magnetic moment of a current loop of area A and current I is:
Answer: a) IA
Explanation: The magnetic moment (μ) of a current loop of area A and current I is given by the formula μ = IA, where I is the current and A is the area of the loop.
The force between two parallel current-carrying wires is:
Answer: a) Proportional to the product of the currents and inversely proportional to the distance between the wires
Explanation: The force (F) between two parallel current-carrying wires is proportional to the product of the currents (I1 and I2) and inversely proportional to the distance (d) between the wires, as described by Ampère’s law.
The magnetic susceptibility of a diamagnetic material is:
Answer: b) Negative
Explanation: The magnetic susceptibility of a diamagnetic material is negative, meaning that the material is slightly repelled by an external magnetic field.

Modern Physics

The de Broglie wavelength of a particle with momentum p is given by
a) h/p
b) p/h
c) h^2/p
d) p^2/h
The energy of a photon is given by the formula
a) E = hf
b) E = h/f
c) E = h^2/f
d) E = f/h
The Compton effect is the
a) Increase in the wavelength of a photon after it interacts with a free electron
b) Decrease in the wavelength of a photon after it interacts with a free electron
c) Increase in the energy of a photon after it interacts with a free electron
d) Decrease in the energy of a photon after it interacts with a free electron
The half-life of a radioactive substance is the time in which
a) Half the nuclei decay
b) One-fourth the nuclei decay
c) Three-fourths the nuclei decay
d) One-eighth the nuclei decay The de Broglie wavelength of a particle with momentum p is given by

a) h/p
b) p/h
c) h^2/p
d) p^2/h
The energy of a photon is given by the formula
a) E = hf
b) E = h/f
c) E = h^2/f
d) E = f/h
The Compton effect is the
a) Increase in the wavelength of a photon after it interacts with a free electron
b) Decrease in the wavelength of a photon after it interacts with a free electron
c) Increase in the energy of a photon after it interacts with a free electron
d) Decrease in the energy of a photon after it interacts with a free electron
The half-life of a radioactive substance is the time in which
a) Half the nuclei decay
b) One-fourth the nuclei decay
c) Three-fourths the nuclei decay
d) One-eighth the nuclei decay
The de Broglie wavelength of a particle with momentum p is given by:
Answer: a) h/p
Explanation: The de Broglie wavelength (λ) of a particle with momentum p is given by the formula λ = h/p, where h is the Planck constant.
The energy of a photon is given by the formula:
Answer: a) E = hf
Explanation: The energy (E) of a photon is given by the formula E = hf, where h is the Planck constant and f is the frequency of the photon.
The Compton effect is the:
Answer: a) Increase in the wavelength of a photon after it interacts with a free electron
Explanation: The Compton effect is the increase in the wavelength of a photon after it interacts with a free electron, as the photon transfers some of its energy and momentum to the electron.
The half-life of a radioactive substance is the time in which:
Answer: a) Half the nuclei decay
Explanation: The half-life of a radioactive substance is the time it takes for half the radioactive nuclei to decay.

Optics

The fringe width in a Young’s double-slit experiment with slit separation d and screen-slit distance D is given by
a) Δy = λD/d
b) Δy = λd/D
c) Δy = λ/d
d) Δy = λD/2d
The power of a combination of a convex lens of focal length f and a concave lens of focal length -f placed in contact is
a) 0
b) 1/f
c) 2/f
d) -1/f
The magnifying power of a compound microscope with an objective lens of focal length f1 and an eyepiece of focal length f2 is given by
a) M = f2/f1
b) M = f1/f2
c) M = (f1+f2)/f1f2
d) M = (f1+f2)/f1
The refractive index of a medium is given by the formula
a) n = c/v
b) n = v/c
c) n = 1/c
d) n = 1/v
The fringe width in a Young’s double-slit experiment with slit separation d and screen-slit distance D is given by:
Answer: a) Δy = λD/d
Explanation: The fringe width (Δy) in a Young’s double-slit experiment is given by the formula Δy = λD/d, where λ is the wavelength of the light, D is the distance between the screen and the slits, and d is the separation between the slits.
The power of a combination of a convex lens of focal length f and a concave lens of focal length -f placed in contact is:
Answer: a) 0
Explanation: When a convex lens of focal length f and a concave lens of focal length -f are placed in contact, the power of the combination is zero, as the positive power of the convex lens is canceled out by the negative power of the concave lens.
The magnifying power of a compound microscope with an objective lens of focal length f1 and an eyepiece of focal length f2 is given by:
Answer: a) M = f2/f1
Explanation: The magnifying power (M) of a compound microscope is given by the formula M = f2/f1, where f1 is the focal length of the objective lens and f2 is the focal length of the eyepiece.
The refractive index of a medium is given by the formula:
Answer: a) n = c/v
Explanation: The refractive index (n) of a medium is given by the formula n = c/v, where c is the speed of light in a vacuum and v is the speed of light in the medium.

Current Electricity

In a series RLC circuit, the current lags the voltage by an angle θ. The value of tan(θ) is:
Answer: a) ωL/R
Explanation: In a series RLC circuit, the current lags the voltage by an angle θ, and the value of tan(θ) is given by the formula: tan(θ) = ωL/R, where ω is the angular frequency, L is the inductance, and R is the resistance.
The equivalent resistance of a wire of resistance R cut into n equal parts and connected in parallel is:
Answer: a) R/n
Explanation: The equivalent resistance of n resistors of equal resistance R connected in parallel is given by the formula: R_eq = R/n, where n is the number of resistors.
The potential difference between the ends of a potentiometer wire connected to a cell of emf E and internal resistance r is:
Answer: b) E/(1+r/R)
Explanation: The potential difference between the ends of a potentiometer wire connected to a cell of emf E and internal resistance r is given by the formula: V = E/(1+r/R), where R is the resistance of the potentiometer wire.
In a series RLC circuit, the current lags the voltage by an angle θ. The value of tan(θ) is:
Answer: a) ωL/R
Explanation: In a series RLC circuit, the current lags the voltage by an angle θ, and the value of tan(θ) is given by the formula: tan(θ) = ωL/R, where ω is the angular frequency, L is the inductance, and R is the resistance.
The equivalent resistance of a wire of resistance R cut into n equal parts and connected in parallel is:
Answer: a) R/n
Explanation: The equivalent resistance of n resistors of equal resistance R connected in parallel is given by the formula: R_eq = R/n, where n is the number of resistors.
The potential difference between the ends of a potentiometer wire connected to a cell of emf E and internal resistance r is:
Answer: b) E/(1+r/R)
Explanation: The potential difference between the ends of a potentiometer wire connected to a cell of emf E and internal resistance r is given by the formula: V = E/(1+r/R), where R is the resistance of the potentiometer wire.
In a series RLC circuit, the current lags the voltage by an angle θ. The value of tan(θ) is:
a) ωL/R
b) R/ωL
c) ωC/R
d) R/ωCAnswer: a) ωL/R
Explanation: In a series RLC circuit, the current lags the voltage by an angle θ, and the value of tan(θ) is given by the formula: tan(θ) = ωL/R, where ω is the angular frequency, L is the inductance, and R is the resistance.
The equivalent resistance of a wire of resistance R cut into n equal parts and connected in parallel is:
a) R/n
b) nR
c) R/n^2
d) n^2RAnswer: a) R/n
Explanation: The equivalent resistance of n resistors of equal resistance R connected in parallel is given by the formula: R_eq = R/n, where n is the number of resistors.
The potential difference between the ends of a potentiometer wire connected to a cell of emf E and internal resistance r is:
a) E
b) E/(1+r/R)
c) E/(1+R/r)
d) E/(1+R/2r)Answer: b) E/(1+r/R)
Explanation: The potential difference between the ends of a potentiometer wire connected to a cell of emf E and internal resistance r is given by the formula: V = E/(1+r/R), where R is the resistance of the potentiometer wire.
In a series circuit with a resistor R, an inductor L, and a capacitor C, the current lags the voltage by an angle θ. The value of tan(θ) is1 2 4 5
a) ωL/R
b) R/ωL
c) ωC/R
d) R/ωC
A wire of resistance R is cut into n equal parts and these parts are connected in parallel. The equivalent resistance of the parallel combination is1 2 4 5
a) R/n
b) nR
c) R/n^2
d) n^2R
In a potentiometer experiment, a cell of emf E and internal resistance r is connected to the potentiometer wire. The potential difference between the ends of the potentiometer wire is1 2 4 5
a) E
b) E/(1+r/R)
c) E/(1+R/r)
d) E/(1+R/2r)
The equivalent resistance of a wire of resistance R cut into n equal parts and connected in parallel is
a) R/n
b) nR
c) R/n^2
d) n^2R
The potential difference between the ends of a potentiometer wire connected to a cell of emf E and internal resistance r is given by
a) V = E
b) V = E/(1+r/R)
c) V = E/(1+R/r)
d) V = E/(1+R/2r)
The current lags the voltage by an angle θ in a series RLC circuit, and the value of tan(θ) is
a) tan(θ) = ωL/R
b) tan(θ) = R/ωL
c) tan(θ) = ωC/R
d) tan(θ) = R/ωC
The power dissipated in a resistor of resistance R carrying a current I is given by
a) P = I^2R
b) P = I/R
c) P = IR^2
d) P = I/R^2
The equivalent resistance of a wire of resistance R cut into n equal parts and connected in parallel is:
Answer: a) R/n
Explanation: The equivalent resistance (R_eq) of n resistors of equal resistance R connected in parallel is given by the formula R_eq = R/n.
The potential difference between the ends of a potentiometer wire connected to a cell of emf E and internal resistance r is given by:
Answer: b) V = E/(1+r/R)
Explanation: The potential difference (V) between the ends of a potentiometer wire connected to a cell of emf E and internal resistance r is given by the formula V = E/(1+r/R), where R is the resistance of the potentiometer wire.
The current lags the voltage by an angle θ in a series RLC circuit, and the value of tan(θ) is:
Answer: a) tan(θ) = ωL/R
Explanation: In a series RLC circuit, the current lags the voltage by an angle θ, and the value of tan(θ) is given by the formula tan(θ) = ωL/R, where ω is the angular frequency, L is the inductance, and R is the resistance.
The power dissipated in a resistor of resistance R carrying a current I is given by:
Answer: a) P = I^2R

Modern Physics

The de Broglie wavelength of an electron accelerated through a potential difference V is:
Answer: a) h/√(2meV)
Explanation: The de Broglie wavelength of an electron accelerated through a potential difference V is given by the formula: λ = h/√(2meV), where h is the Planck constant, m is the mass of the electron, and e is the charge of the electron.
The momentum of a photon with energy hf is:
Answer: c) hf/λ
Explanation: The momentum of a photon is given by the formula: p = h/λ, where h is the Planck constant and λ is the wavelength of the photon. Since the energy of the photon is hf, the momentum can be expressed as p = hf/λ.
The half-life of a radioactive substance with a decay constant λ is:
Answer: a) ln(2)/λ
Explanation: The half-life of a radioactive substance is the time it takes for the number of radioactive nuclei to decrease to half of its initial value. The half-life is given by the formula: t1/2 = ln(2)/λ, where λ is the decay constant of the radioactive substance.
The de Broglie wavelength of an electron accelerated through a potential difference V is1 2 4 5
a) h/√(2meV)
b) h/√(meV)
c) h/√(meV/2)
d) h/√(2meV/h^2)
The momentum of a photon with energy hf is1 2 4 5
a) hf/c
b) h/λ
c) hf/λ
d) h/f
The half-life of a radioactive substance with a decay constant λ is1 2 4 5
a) ln(2)/λ
b) 1/λ
c) 2/λ
d) ln(2)/2λ
The de Broglie wavelength of an electron accelerated through a potential difference V is:
Answer: a) h/√(2meV)
Explanation: The de Broglie wavelength of an electron accelerated through a potential difference V is given by the formula: λ = h/√(2meV), where h is the Planck constant, m is the mass of the electron, and e is the charge of the electron.
The momentum of a photon with energy hf is:
Answer: c) hf/λ
Explanation: The momentum of a photon is given by the formula: p = h/λ, where h is the Planck constant and λ is the wavelength of the photon. Since the energy of the photon is hf, the momentum can be expressed as p = hf/λ.
The half-life of a radioactive substance with a decay constant λ is:
Answer: a) ln(2)/λ
Explanation: The half-life of a radioactive substance is the time it takes for the number of radioactive nuclei to decrease to half of its initial value. The half-life is given by the formula: t1/2 = ln(2)/λ, where λ is the decay constant of the radioactive substance.
The de Broglie wavelength of a particle with momentum p is given by:
Answer: a) h/p
Explanation: The de Broglie wavelength (λ) of a particle with momentum p is given by the formula λ = h/p, where h is the Planck constant.
The energy of a photon is given by the formula:
Answer: a) E = hf
Explanation: The energy (E) of a photon is given by the formula E = hf, where h is the Planck constant and f is the frequency of the photon.
The Compton effect is the:
Answer: a) Increase in the wavelength of a photon after it interacts with a free electron
Explanation: The Compton effect is the increase in the wavelength of a photon after it interacts with a free electron, as the photon transfers some of its energy and momentum to the electron.
The half-life of a radioactive substance is the time in which:
Answer: a) Half the nuclei decay
Explanation: The half-life of a radioactive substance is the time it takes for half the radioactive nuclei to decay.

Thermodynamics

The work done in an isothermal process is given by the formula
a) W = PΔV
b) W = -PΔV
c) W = nRΔT
d) W = 0
The efficiency of a Carnot engine operating between two reservoirs at temperatures T1 and T2 (T1 > T2) is given by
a) η = 1 – T2/T1
b) η = T1/T2
c) η = T2/T1
d) η = 1 – T1/T2
The mean free path of a gas molecule is inversely proportional to
a) The square root of the pressure
b) The pressure
c) The square of the pressure
d) The cube of the pressure
The work done in the isothermal expansion of an ideal gas from volume V1 to volume V2 is given by the formula
a) W = nRT ln(V2/V1)
b) W = -nRT ln(V2/V1)
c) W = nRT(V2-V1)
d) W = -nRT(V2-V1)
The work done by a system in an isothermal process is1 2 4 5
a) Zero
b) PΔV
c) -PΔV
d) nRΔT
The efficiency of a Carnot engine operating between two reservoirs at temperatures T1 and T2 (T1 > T2) is1 2 4 5
a) 1 – T2/T1
b) T1/T2
c) T2/T1
d) 1 – T1/T2
The mean free path of a gas molecule is inversely proportional to1 2 4 5
a) The square root of the pressure
b) The pressure
c) The square of the pressure
d) The cube of the pressure
The work done in the isothermal expansion of an ideal gas from volume V1 to volume V2 is1 2 4 5
a) nRT ln(V2/V1)
b) -nRT ln(V2/V1)
c) nRT(V2-V1)
d) -nRT(V2-V1)
The work done in an isothermal process is given by the formula:
Answer: b) W = -PΔV
Explanation: The work done (W) in an isothermal process is given by the formula W = -PΔV, where P is the pressure and ΔV is the change in volume.
The efficiency of a Carnot engine operating between two reservoirs at temperatures T1 and T2 (T1 > T2) is given by:
Answer: a) η = 1 – T2/T1
Explanation: The efficiency (η) of a Carnot engine operating between two reservoirs at temperatures T1 and T2 (T1 > T2) is given by the formula η = 1 – T2/T1.
The mean free path of a gas molecule is inversely proportional to:
Answer: b) The pressure
Explanation: The mean free path of a gas molecule is inversely proportional to the pressure of the gas, as the higher the pressure, the more collisions the gas molecules will experience, resulting in a shorter mean free path.
The work done in the isothermal expansion of an ideal gas from volume V1 to volume V2 is given by the formula:
Answer: a) W = nRT ln(V2/V1)
Explanation: The work done (W) in the isothermal expansion of an ideal gas from volume V1 to volume V2 is given by the formula W = nRT ln(V2/V1), where n is the number of moles of the gas, R is the universal gas constant, and T is the absolute temperature.
The work done by a system in an isothermal process is:
Answer: c) -PΔV
Explanation: In an isothermal process, the work done by the system is given by the formula: W = -PΔV, where P is the pressure and ΔV is the change in volume.
The efficiency of a Carnot engine operating between two reservoirs at temperatures T1 and T2 (T1 > T2) is:
Answer: a) 1 – T2/T1
Explanation: The efficiency of a Carnot engine operating between two reservoirs at temperatures T1 and T2 (T1 > T2) is given by the formula: η = 1 – T2/T1, where T1 is the temperature of the hot reservoir and T2 is the temperature of the cold reservoir.
The mean free path of a gas molecule is inversely proportional to:
Answer: b) The pressure
Explanation: The mean free path of a gas molecule is inversely proportional to the pressure of the gas, as the higher the pressure, the more collisions the gas molecules will experience, resulting in a shorter mean free path.
The work done in the isothermal expansion of an ideal gas from volume V1 to volume V2 is:
Answer: a) nRT ln(V2/V1)
Explanation: The work done in the isothermal expansion of an ideal gas from volume V1 to volume V2 is given by the formula: W = nRT ln(V2/V1), where n is the number of moles of the gas, R is the universal gas constant, and T is the absolute temperature.
Okay, based on the search results provided, here are 100 complex NEET Physics questions covering all sections as per the NEET 2024 weightage, with answers and explanations:
The work done in an isothermal process is given by the formula:
Answer: b) W = -PΔV
Explanation: The work done (W) in an isothermal process is given by the formula W = -PΔV, where P is the pressure and ΔV is the change in volume.
The efficiency of a Carnot engine operating between two reservoirs at temperatures T1 and T2 (T1 > T2) is given by:
Answer: a) η = 1 – T2/T1
Explanation: The efficiency (η) of a Carnot engine operating between two reservoirs at temperatures T1 and T2 (T1 > T2) is given by the formula η = 1 – T2/T1.
The mean free path of a gas molecule is inversely proportional to:
Answer: b) The pressure
Explanation: The mean free path of a gas molecule is inversely proportional to the pressure of the gas, as the higher the pressure, the more collisions the gas molecules will experience, resulting in a shorter mean free path.
The work done in the isothermal expansion of an ideal gas from volume V1 to volume V2 is given by the formula:
Answer: a) W = nRT ln(V2/V1)
Explanation: The work done (W) in the isothermal expansion of an ideal gas from volume V1 to volume V2 is given by the formula W = nRT ln(V2/V1), where n is the number of moles of the gas, R is the universal gas constant, and T is the absolute temperature.

The work done by a system in an isothermal process is:
Answer: c) -PΔV
Explanation: In an isothermal process, the work done by the system is given by the formula: W = -PΔV, where P is the pressure and ΔV is the change in volume.
The efficiency of a Carnot engine operating between two reservoirs at temperatures T1 and T2 (T1 > T2) is:
Answer: a) 1 – T2/T1
Explanation: The efficiency of a Carnot engine operating between two reservoirs at temperatures T1 and T2 (T1 > T2) is given by the formula: η = 1 – T2/T1, where T1 is the temperature of the hot reservoir and T2 is the temperature of the cold reservoir.
The mean free path of a gas molecule is inversely proportional to:
Answer: b) The pressure
Explanation: The mean free path of a gas molecule is inversely proportional to the pressure of the gas, as the higher the pressure, the more collisions the gas molecules will experience, resulting in a shorter mean free path.
The work done in the isothermal expansion of an ideal gas from volume V1 to volume V2 is:
Answer: a) nRT ln(V2/V1)
Explanation: The work done in the isothermal expansion of an ideal gas from volume V1 to volume V2 is given by the formula: W = nRT ln(V2/V1), where n is the number of moles of the gas, R is the universal gas constant, and T is the absolute temperature.

Waves and Oscillations(Q4)

The time period of a simple pendulum is proportional to:
Answer: a) √(l/g)
Explanation: The time period (T) of a simple pendulum is given by the formula T = 2π√(l/g), where l is the length of the pendulum and g is the acceleration due to gravity. Therefore, the time period is proportional to √(l/g).
The speed of a transverse wave on a string is given by:
Answer: a) √(T/μ)
Explanation: The speed (v) of a transverse wave on a string is given by the formula v = √(T/μ), where T is the tension in the string and μ is the mass per unit length of the string.
The fundamental frequency of a closed organ pipe is:
Answer: a) v/4L
Explanation: The fundamental frequency (f) of a closed organ pipe is given by the formula f = v/4L, where v is the speed of sound in the medium and L is the length of the pipe.
The quality factor (Q) of an oscillating system is defined as:
Answer: a) ω/Δω
Explanation: The quality factor (Q) of an oscillating system is defined as the ratio of the angular frequency (ω) to the bandwidth (Δω) of the system.

Gravitation ( Q4)

The gravitational potential energy of a particle of mass m at a distance r from the center of a spherical mass M is:
Answer: a) -GMm/r
Explanation: The gravitational potential energy (U) of a particle of mass m at a distance r from the center of a spherical mass M is given by the formula U = -GMm/r, where G is the gravitational constant.
The escape velocity of a particle from the surface of a planet of mass M and radius R is:
Answer: a) √(2GM/R)
Explanation: The escape velocity (v_e) of a particle from the surface of a planet of mass M and radius R is given by the formula v_e = √(2GM/R), where G is the gravitational constant.
The time period of a satellite in a circular orbit around the Earth is:
Answer: a) 2π√(r^3/GM)
Explanation: The time period (T) of a satellite in a circular orbit around the Earth is given by the formula T = 2π√(r^3/GM), where r is the radius of the orbit and M is the mass of the Earth.
The gravitational force between two masses M1 and M2 separated by a distance r is:
Answer: b) GM1M2/r^2
Explanation: The gravitational force (F) between two masses M1 and M2 separated by a distance r is given by the formula F = GM1M2/r^2, where G is the gravitational constant.

Atomic Physics

The radius of the nth Bohr orbit of a hydrogen atom is proportional to:
Answer: d) 1/n
Explanation: The radius (r_n) of the nth Bohr orbit of a hydrogen atom is proportional to 1/n, where n is the principal quantum number.
The energy of an electron in the nth Bohr orbit of a hydrogen atom is proportional to:
Answer: a) -1/n^2
Explanation: The energy (E_n) of an electron in the nth Bohr orbit of a hydrogen atom is proportional to -1/n^2, where n is the principal quantum number.
The angular momentum of an electron in the nth Bohr orbit of a hydrogen atom is proportional to:
Answer: a) n
Explanation: The angular momentum (L) of an electron in the nth Bohr orbit of a hydrogen atom is proportional to n, where n is the principal quantum number.
The wavelength of the Lyman series of the hydrogen atom is given by the Rydberg formula as:
Answer: a) 1/[1/1^2 – 1/n^2]
Explanation: The wavelength (λ) of the Lyman series of the hydrogen atom is given by the Rydberg formula λ = 1/[1/1^2 – 1/n^2], where n is the principal quantum number.

Nuclear Physics

The binding energy per nucleon of a nucleus is given by the formula:
Answer: a) BE/A = a – b(A-2Z)^2/A
Explanation: The binding energy per nucleon (BE/A) of a nucleus is given by the formula BE/A = a – b(A-2Z)^2/A, where A is the mass number, Z is the atomic number, and a and b are constants.
The half-life of a radioactive substance is the time in which:
Answer: a) Half the nuclei decay
Explanation: The half-life of a radioactive substance is the time it takes for half the radioactive nuclei to decay.
The activity of a radioactive substance is proportional to:
Answer: a) The number of radioactive nuclei
Explanation: The activity (A) of a radioactive substance is proportional to the number of radioactive nuclei present.
The energy released in a nuclear fission reaction is primarily due to the:
Answer: a) Conversion of mass to energy
Explanation: The energy released in a nuclear fission reaction is primarily due to the conversion of a small amount of mass into a large amount of energy, as described by Einstein’s famous equation E =mc2

Semiconductor Electronics

The energy band gap of a semiconductor is:
Answer: a) The energy difference between the conduction band and the valence band
Explanation: The energy band gap of a semiconductor is the energy difference between the conduction band and the valence band, which determines the electrical and optical properties of the material.
The majority charge carriers in an n-type semiconductor are:
Answer: a) Electrons
Explanation: In an n-type semiconductor, the majority charge carriers are electrons, which are introduced by doping the semiconductor with impurities that have a surplus of electrons.
The forward bias current in a p-n junction diode is primarily due to the:
Answer: c) Diffusion of majority charge carriers
Explanation: In a forward-biased p-n junction diode, the current is primarily due to the diffusion of majority charge carriers (electrons in the n-type region and holes in the p-type region) across the junction.
The output voltage of a common emitter amplifier is:
Answer: b) Out of phase with the input voltage
Explanation: In a common emitter amplifier, the output voltage is 180 degrees out of phase with the input voltage, meaning that the output voltage is inverted compared to the input voltage.

Electromagnetic Induction

The induced emf in a coil of N turns and area A, placed in a time-varying magnetic field B, is given by:
Answer: a) -NAΔB/Δt
Explanation: The induced emf (ε) in a coil of N turns and area A, placed in a time-varying magnetic field B, is given by Faraday’s law of electromagnetic induction: ε = -NAΔB/Δt, where ΔB is the change in the magnetic field over time Δt.
The self-inductance of a solenoid of length l, cross-sectional area A, and number of turns N is proportional to:
Answer: a) N^2/l
Explanation: The self-inductance (L) of a solenoid is proportional to the square of the number of turns (N^2) divided by the length of the solenoid (l).
The mutual inductance between two coils is proportional to:
Answer: a) The number of turns in each coil
Explanation: The mutual inductance (M) between two coils is proportional to the number of turns (N) in each coil, as the induced emf in one coil is due to the changing magnetic field produced by the current in the other coil.
The eddy currents induced in a conducting material are:
Answer: a) Proportional to
The induced emf in a coil of N turns and area A, placed in a time-varying magnetic field B, is given by:
Answer: a) -NAΔB/Δt
Explanation: The induced emf (ε) in a coil of N turns and area A, placed in a time-varying magnetic field B, is given by Faraday’s law of electromagnetic induction: ε = -NAΔB/Δt, where ΔB is the change in the magnetic field over time Δt.
The self-inductance of a solenoid of length l, cross-sectional area A, and number of turns N is proportional to:
Answer: a) N^2/l
Explanation: The self-inductance (L) of a solenoid is proportional to the square of the number of turns (N^2) divided by the length of the solenoid (l).
The mutual inductance between two coils is proportional to:
Answer: a) The number of turns in each coil
Explanation: The mutual inductance (M) between two coils is proportional to the number of turns (N) in each coil, as the induced emf in one coil is due to the changing magnetic field produced by the current in the other coil.
The eddy currents induced in a conducting material are:
Answer: a) Proportional to the rate of change of the magnetic field
Explanation: Eddy currents induced in a conducting material are proportional to the rate of change of the magnetic field, as described by Faraday’s law of electromagnetic induction.

Dual Nature of Matter and Radiation

The de Broglie wavelength of a particle with momentum p is:
Answer: a) h/p
Explanation: The de Broglie wavelength (λ) of a particle with momentum p is given by the formula λ = h/p, where h is the Planck constant.The photoelectric effect is characterized by:
Answer: a) The emission of electrons from a metal surface when exposed to light
Explanation: The photoelectric effect is the emission of electrons from a metal surface when it is exposed to light, as the energy of the photons is transferred to the electrons in the metal.
The energy of a photon is given by the formula:
Answer: a) E = hf
Explanation: The energy (E) of a photon is given by the formula E = hf, where h is the Planck constant and f is the frequency of the photon.

The Compton effect is the:
Answer: a) Increase in the wavelength of a photon after it interacts with a free electron
Explanation: The Compton effect is the increase in the wavelength of a photon after it interacts with a free electron, as the photon transfers some of its energy and momentum to the