Let \(I_1\) and \(I_2\) be the moments of inertia of two bodies of identical geometrical shape, the first made of aluminium and the second of iron:
1. | \(I_1 <I_2\) |
2. | \(I_1 = I_2\) |
3. | \(I_1>I_2\) |
4. | \(I_1\) and \(I_2\) depends on the actual shapes of the bodies | The relation between
A body having its centre of mass at the origin has three of its particles at (a, 0, 0), (0, a, 0), (0, 0, a). The moments of inertia of the body about the X and Y axes are 0.20 kg-m2 each. The moment of inertia about the Z-axis:
1. is 0.20 kg-m2
2. is 0.40 kg-m2
3. is \(0.20\sqrt2\) kg-m2
4. cannot be deduced with this information
A cubical block of mass M and edge a slides down a rough inclined plane of inclination θ with a uniform velocity. The torque of the normal force on the block about its centre has a magnitude
1. zero
2. Mga
3. Mga sin θ
4. \(\frac{1}{2}\) Mga sin θ
A thin circular ring of mass \(M\) and radius \(r\) is rotating about its axis with an angular speed \(\omega\). Two particles having mass \(m\) each are now attached at diametrically opposite points. The angular speed of the ring will become:
1. \(\frac{\omega M}{M+m}\)
2. \(\frac{\omega M}{M+2 m}\)
3. \(\frac{\omega(M-2 m)}{M+2 m}\)
4. \(\frac{\omega(M+2 m)}{M}\)
A person sitting firmly over a rotating stool has his arms stretched. If he folds his arms, his angular momentum about the axis of rotation:
1. | increases | 2. | decreases |
3. | remains unchanged | 4. | doubles |
The axis of rotation of a purely rotating body:
a. | must pass through the centre of mass |
b. | may pass through the centre of mass |
c. | must pass through a particle of the body |
d. | may pass through a particle of the body |
Choose the correct option:
1. | (a) and (b) |
2. | (b) and (d) |
3. | (a) and (c) |
4. | (a), (b) and (d) |
Consider the following two equations
(A) L = I ω (B) \(\frac{dL}{dt}=\Gamma\)
In noninertial frames:
1. both A and B are true
2. A is true but B is false
3. B is true but A is false
4. both A and B are false
A particle moves on a straight line with a uniform velocity. Its angular momentum:
(a) | is always zero. |
(b) | is zero about a point on the straight line. |
(c) | is not zero about a point away from the straight line. |
(d) | about any given point remains constant. |
Choose the correct option:
1. | (a), (b) and (c) | 2. | (a), (b) and (d) |
3. | (b), (c) and (d) | 4. | none of these |
If there is no external force acting on a non-rigid body which of the following quantities must remain constant?
a. | angular momentum |
b. | linear momentum |
c. | kinetic energy |
d. | moment of inertia |
1. | (a) and (b) |
2. | (b) and (c) |
3. | (c) and (d) |
4. | (a) and (d) |
Let IA and IB be moments of inertia of a body about two axes A and B respectively. The axis A passes through the centre of mass of the body but B does not.
1. IA < IB
2. If IA < IB, the axes are parallel
3. If the axes are parallel, IA < IB
4. If the axes are not parallel, IA ≥ IB