A Solid sphere and solid cylinder of identical radii approach an incline with the same linear velocity (See figure). Both roll without slipping all throughout. The two climb maximum heights \(h_s\) and \(h_c\) on the incline. The ratio \(\frac{h_{s}}{h_{c}}\) is given by:

          
1. \( \frac{2}{\sqrt{5}} \)
2. \( \frac{14}{15} \)
3. \(\frac{4}{5} \)
4. \( 1\)

Subtopic:  Rotational Motion: Kinematics |
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A stationary horizontal disc is free to rotate about its axis. When a torque is applied on it, its kinetic energy as a function of \(\theta,\) where \(\theta\) is the angle by which it has rotated, is given as \(k\theta^2\) (where \(k\) is constant). If its moment of inertia is \(I,\) then the angular acceleration of the disc is:
1. \(\frac{k}{I} \theta\)

2. \(\frac{k}{2 I} \theta\)

3. \(\frac{k}{4 I} \theta\)

4. \(\frac{2 k}{I} \theta\)

Subtopic:  Rotational Motion: Kinematics |
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The moment of inertia of a body about a given axis is \(1.5\) kg-m2. Initially, the body is at rest. In order to produce rotational kinetic energy of \(1200\) J, the angular acceleration of \(20\) rad/s2 must be applied about the axis for a duration of:
1. \(5\) s
2. \(3\) s
3. \(2.5\) s
4. \(2\) s

Subtopic:  Rotational Motion: Kinematics |
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A cord is wound around the circumference of the wheel of radius \(r.\) The axis of the wheel is horizontal and the moment of inertia about it is \(I.\) A weight \(mg\) is attached to the cord at the end. The weight falls from rest. After falling through a distance \('h',\) the square of the angular velocity of the wheel will be:
1. \( \dfrac{2 m g h}{I+2 m r^2} \)

2. \( \dfrac{2 m g h}{I+m r^2} \)

3. \( 2 g h\)

4. \( \dfrac{2 g h}{I+m r^2} \)

Subtopic:  Rotational Motion: Kinematics |
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A flywheel is accelerated uniformly from rest and rotates through \(5\) rad in the first second. The angle rotated by the flywheel in the next second will be: 
1. \(7.5\) rad  2. \(15\) rad 
3. \(20\) rad  4. \(30\) rad 
Subtopic:  Rotational Motion: Kinematics |
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A ball is spun with angular acceleration \(\alpha=6 {t}^2-2 {t}\) where \(t\) is in seconds and \(\alpha\) is in rad/s2. At \(t=0\), the ball has angular velocity of \(10\) rad/s and angular position of \(4\) rad. The most appropriate expression for the angular position of the ball is:
1. \( \dfrac{3}{2} t^4-t^2+10 t \) 2. \(\dfrac{t^4}{2}-\dfrac{t^3}{3}+10 t+4 \)
3. \( \dfrac{2 t^4}{3}-\dfrac{t^3}{6}+10 t+12 \) 4. \( 2 t^4-\dfrac{t^3}{2}+5 t+4\)
Subtopic:  Rotational Motion: Kinematics |
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A body is rotating with kinetic energy, \(E.\) If the angular velocity of the body is increased to three times of the initial angular velocity then kinetic energy becomes \(nE.\) What would be the value of \(n?\)
1. \(3\)
2. \(7\)
3. \(9\)
4. \(5\)
Subtopic:  Rotational Motion: Kinematics |
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