The centre of a wheel rolling on a plane surface moves with a speed \(v_0.\) A particle on the rim of the wheel at the same level as the centre will be moving at speed:
1. zero
2. \(v_0\)
3. \(\sqrt{2}v_0\)
4. \(2v_0\)

 62%
Level 2: 60%+
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Moment of inertia of a uniform cylinder of mass M, radius R and length l about an axis passing through its center and normal to its axis would be

1.  Ml212

2.  MR22

3.  Ml212+R24

4.  Ml212+R22

Subtopic:  Moment of Inertia |
 58%
Level 3: 35%-60%
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A particle moves along a circle of radius 20πm with constant tangential acceleration. If the velocity of the particle is 80 m/s at the end of the second revolution after motion has begin, the tangential acceleration is

1. 640 πm/s2

2. 160 πm/s2

3. 40 πm/s2

4. 40 m/s2

Subtopic:  Rotational Motion: Kinematics |
 58%
Level 3: 35%-60%
PMT - 2003
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If the radius of the earth is suddenly contracted to half of its present value, then the duration of the day will be of:

1. 6 hours 2. 12 hours
3. 18 hours 4. 24 hours
Subtopic:  Angular Momentum |
 71%
Level 2: 60%+
PMT - 1999
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A wheel has angular acceleration of 3.0 rad/sec2 and an initial angular speed of 2.00 rad/sec.  In a time of 2 sec it has rotated through an angle (in radian) of 

1. 10               

2. 12

3. 4                 

4. 6

Subtopic:  Rotational Motion: Kinematics | Torque |
 82%
Level 1: 80%+
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If a force acts on a body at a point away from the centre-of-mass, then:

1. Linear acceleration changes 
2. Angular acceleration changes 
3. Both change 
4. None of these
Subtopic:  Torque |
 60%
Level 2: 60%+
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If the linear density of a rod of length \(3~ \text{m}\) varies as \(\lambda=2+x,\) then the position of the centre-of-mass of the rod is at a distance of:
1. \(\dfrac{7}{3}~\text{m}\) 2. \(\dfrac{10}{7}~\text{m}\)
3. \(\dfrac{12}{7}~\text{m}\) 4. \(\dfrac{9}{7}~\text{m}\)
Subtopic:  Center of Mass |
 68%
Level 2: 60%+
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A sphere can not roll on:

1.  a smooth horizontal surface 

2.  a rough horizontal surface 

3.  a smooth inclined surface 

4.  a rough inclined surface 

 55%
Level 3: 35%-60%
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Two balls are thrown simultaneously in the air. The acceleration of the centre-of-mass of the two balls while in the air:

1. depends on the direction of the motion of the balls
2. depends on the masses of the two balls 
3. depends on the speeds of two balls 
4. is equal to \(g\)
Subtopic:  Center of Mass |
 69%
Level 2: 60%+
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A cord is wound round the circumference of wheel of radius r. The axis of the wheel is horizotal and moment of inertia about it is I. A weight mg is attached to the end of the cord and falls from rest. After falling through a distance h, the angular velocity of the wheel will be

1. 2ghI+mr

2. 2mghI+mr2

3. 2mghI+2m12

4. 2gh

 73%
Level 2: 60%+
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