NEET Physics Moment of Inertia and Rotational K E MCQs Set A

a) planar, perpendicular and perpendicular

b) three dimensional, parallel and perpendicular

c) planar, perpendicular and parallel

d) three dimensional, perpendicular and perpendicular

Answer: planar, perpendicular and perpendicular

Question:  The moment of inertia of a uniform circular disc of radius ‘R’ and mass ‘M’ about an axis passing from the edge of the disc and normal to the disc is

a)

b)

c)

d)

Answer:

Question: Moment of inertia does not depend upon

a) point of application of force

b) None of these

c) axis of rotation

d) distribution of mass

Answer: point of application of force

Question: Moment of inertia of a circular wire of mass M and radius R about its diameter is

a) MR²/2

b) MR²

c) 2MR²

d) MR²/4

Answer:  MR²/2

Question:  Moment of inertia of a hollow cylinder of mass M and radius r about its own axis is

a) Mr²

b)

c)

d)

Answer: Mr²

Question: Which of the following has the highest moment of inertia when each of them has the same mass and the same outer radius

a) a ring about its axis, perpendicular to the plane of the ring

b) a disc about its axis, perpendicular to the plane of the ring

c) a solid sphere about one of its diameters

d) a spherical shell about one of its diameters

Answer: a ring about its axis, perpendicular to the plane of the ring

Question: Radius of gyration of a body depends upon

a) axis of rotation

b) translational motion

c) area of the body

d) shape of the body

Answer: axis of rotation

Question:  The correct relation between moment of inertia I, radius of gyration k and mass M of the body is

a)

b)

c)

d) None of these

Answer:

Question:  If two circular discs A and B are of same mass but of radii r and 2r respectively, then the moment of inertia of A is

a) 1/4 that of B

b) twice that of B

c) the same as that of B

d) four times that of B

Answer: 1/4 that of B

Question: For a given mass and size, moment of inertia of a solid disc is

a) less than that of a ring

b) equal to that of a ring

c) depend on the material of ring and disc

d) more than that of a ring

Answer: less than that of a ring

Question:  What is the moment of inertia of a solid sphere about its diameter?

a)

b)

c)

d)

Answer:

More Questions..........................................................

Question:

a)

b)

c)

d)

Answer:

Question:   The moment of inertia of a uniform circular disc (figure) is maximum about an axis perpendicular to the disc and passing through

a) B

b) C

c) D

d) A

Answer:  B

Question:

a)

b)

c)

d) None of these

Answer:

Question:   The moment of inertia of the rectangular plate ABCD, (AB = 2 BC) is minimum along the axis

a) E F

b) B C

c) A C

d) G H

Answer:  E F

Question: Assertion : If polar ice melts, days will be longer.
Reason :    Moment of inertia decreases and thus angular velocity increases

a) Assertion is correct, reason is incorrect

b) Assertion is incorrect, reason is correct

c) Assertion is correct, reason is correct; reason is not a correct explanation for assertion

d) Assertion is correct, reason is correct; reason is a correct explanation for assertion.

Answer: Assertion is correct, reason is incorrect

Question:  Of the two eggs which have identical sizes, shapes and weights, one is raw, and other is half boiled. The ratio between the moment of inertia of the raw to the half boiled egg about central axis is

a) greater than one

b) not comparable

c) one

d) less than one

Answer: greater than one

Question: One solid sphere A and another hollow sphere B are of same mass and same outer radii, Their moments of inertia about their diameters are respectively I_A and I_B, such that

a) I_A < I_B

b) I_A = I_B

c) I_A > I_B

d) None of these

Answer:  I_A < I_B

Question:  A wheel having moment of inertia 2 kg-m² about its vertical axis, rotates at the rate of 60 rpm about this axis, The torque which can stop the wheel’s rotation in one minute would be

a) 0.21 Nm

b) 0.55 Nm

c) 0.83 Nm

d) 1.12 Nm

Answer:  0.21 Nm

Question:

a)

b)

c)

d) None of these

Answer:

Question:  The ratio of the radii of gyration of a circular disc about a tangential axis in the plane of the disc and of a circular ring of the same radius about a tangential axis in the plane of the ring is

a)

b)

c) 1 : 3

d) 2 : 1

Answer:

Question:  The moment of inertia of a thin uniform rod of mass M and length L about an axis passing through its midpoint and perpendicular to its length is I₀. Its moment of inertia about an axis passing through one of its ends and perpendicular to its length is

a) I₀ + ML²/4

b) I⁰ + ML²

c) I₀ + 2ML²

d) None of these

Answer:  I₀ + ML²/4

Question:

a)

b)

c)

d)

Answer:

Question:  Point masses 1, 2, 3 and 4 kg are lying at the points (0, 0, 0), (2, 0, 0), (0, 3, 0) and (–2, –2, 0) respectively. The moment of inertia of this system about X-axis will be

a) 43 kg m²

b) 34 kg m²

c) 27 kg m²

d) 72 kg m²

Answer: 43 kg m²

Question:  Consider a uniform square plate of side ‘a’ and mass ‘m’. The moment of inertia of this plate about an axis perpendicular to its plane and passing through one of its corners is

a)

b)

c)

d)

Answer:

Question:   The moment of inertia of a circular disc of mass M and radius R about an axis passing through the centre of mass is I0. The moment of inertia of another circular disc of same mass and thickness but half the density about the same axis is

a)

b)

c)

d)

Answer:

Question:  Consider a thin uniform square sheet made of a rigid material. If its side is ‘a’ mass m and moment of inertia I about one of its diagonals, then

a)

b)

c)

d)

Answer:

Question:  From a solid sphere of mass M and radius R a cube of maximum possible volume is cut. Moment of inertia of cube about an axis passing through its center and perpendicular to one of its faces is

a)

b)

c)

d)

Answer:

Question:

a) 0.5 × 10^–3

b) 1.5 × 10^–3

c) 0.25 × 10^–3

d) 1.25 × 10^–3

Answer: 0.5 × 10^–3

Question: Two bodies have their moments of inertia I and 2I respectively about their axis of rotation. If their kinetic energies of rotation are equal, their angular momenta will be in the ratio

a)

b)

c)

d) None of these

Answer:

Question:   M.I of a circular loop of radius R about the axis in figure is

a) (3/4) MR²

b) MR²/2

c) 2MR²

d) MR²

Answer: (3/4) MR²

Question:  A rod of mass m and length l is bent in to shape of L. Its moment of inertia about the axis shown in figure

a)

b)

c)

d) None

Answer:

Question:  The moment of inertia of a hollow thick spherical shell of mass M and its inner radius R₁ and outer radius R₂ about its diameter is

a)

b)

c)

d)

Answer:

Question:

a) 4

b) 5

c) 3

d) 2

Answer: 4

Question:  Four masses are fixed on a massless rod as shown in the adjoining figure. The moment of inertia about the dotted axis is about

a) 1 kg m²

b) 0.5 kg m²

c) 0.3 kg m²

d) 2 kg m²

Answer: 1 kg m²

Question:   A solid cylinder of mass 50 kg and radius 0.5 m is free to rotate about the horizontal axis. A massless string is wound round the cylinder with one end attached to it and other hanging freely. Tension in the string required to produce an angular acceleration of 2 revolutions s^{– 2} is

a) 157 N

b) 78.5 N

c) 50 N

d) 25 N

Answer:  157 N

Question:

a) 10^–6

b) 10^–5

c) 10^–4

d) 10^–8

Answer: 10^–6

Question: The restoring force per unit area is known as

a) stress

b) plasticity

c) elasticity

d) strain

Answer: stress

Question: What is the phenomenon of temporary delay in regaining the original configuration by an elastic body, after the removel of a deforming force?

a) Elastic after effect

b) Elasticity

c) Elastic fatigue

d) Plasticity

Answer:  Elastic after effect