Angular Momentum and its Conservation for a Rigid Body
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PHXI07:SYSTEMS OF PARTICLES AND ROTATIONAL MOTION

365671 A ballet dancer is rotating about his own vertical axis on smooth horizontal floor. \(I\), \(\omega ,L,K\) are moment of inertia, angular velocity, angular momentum, rotational kinetic energy of ballet dancer respectively. If ballet dancer stretches himself away from his axis of rotation then

1 \(I\) increases and \(\omega ,E\) decrease but \(L\) is constant
2 \(I\) decreases, \(\omega\) and \(E\) increase but \(L\) is constant
3 \(I\) increases, \(\omega\) decreases, \(L\) and \(E\) are constant
4 \(I\) increases, \(\omega\) increases but \(L\) and \(E\) are constant
PHXI07:SYSTEMS OF PARTICLES AND ROTATIONAL MOTION

365672 Assertion :
A person standing on a rotating platform suddenly stretched his arms, the platform slows down.
Reason :
A person by stretching his arms increase the moment of inertia and decreases angular velocity.

1 Both Assertion and Reason are correct and Reason is the correct explanation of the Assertion.
2 Both Assertion and Reason are correct but Reason is not the correct explanation of the Assertion.
3 Assertion is correct but Reason is incorrect.
4 Assertion is incorrect but reason is correct.
PHXI07:SYSTEMS OF PARTICLES AND ROTATIONAL MOTION

365673 Assertion :
Moment of inertia is always constant.
Reason :
Angular momentum is conserved if the external torque is zero.

1 Both Assertion and Reason are correct and Reason is the correct explanation of the Assertion.
2 Both Assertion and Reason are correct but Reason is not the correct explanation of the Assertion.
3 Assertion is correct but Reason is incorrect.
4 Assertion is incorrect but reason is correct.
PHXI07:SYSTEMS OF PARTICLES AND ROTATIONAL MOTION

365674 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

1 \(1: 2\)
2 \(\sqrt{2: 1}\)
3 \(1: \sqrt{2}\)
4 \(2: 1\)
PHXI07:SYSTEMS OF PARTICLES AND ROTATIONAL MOTION

365675 A uniform rod \(AB\) mass \(m\) and length \(2 a\) is falling freely without rotation under gravity with \(A B\) horizontal. Suddenly the end \(A\) is fixed when the speed of the rod is \(v\). The angular speed with which the rod begins to rotate is

1 \(\dfrac{v}{3 a}\)
2 \(\dfrac{3 v}{4 a}\)
3 \(\dfrac{4 v}{3 a}\)
4 \(\dfrac{v}{2 a}\)
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PHXI07:SYSTEMS OF PARTICLES AND ROTATIONAL MOTION

365671 A ballet dancer is rotating about his own vertical axis on smooth horizontal floor. \(I\), \(\omega ,L,K\) are moment of inertia, angular velocity, angular momentum, rotational kinetic energy of ballet dancer respectively. If ballet dancer stretches himself away from his axis of rotation then

1 \(I\) increases and \(\omega ,E\) decrease but \(L\) is constant
2 \(I\) decreases, \(\omega\) and \(E\) increase but \(L\) is constant
3 \(I\) increases, \(\omega\) decreases, \(L\) and \(E\) are constant
4 \(I\) increases, \(\omega\) increases but \(L\) and \(E\) are constant
PHXI07:SYSTEMS OF PARTICLES AND ROTATIONAL MOTION

365672 Assertion :
A person standing on a rotating platform suddenly stretched his arms, the platform slows down.
Reason :
A person by stretching his arms increase the moment of inertia and decreases angular velocity.

1 Both Assertion and Reason are correct and Reason is the correct explanation of the Assertion.
2 Both Assertion and Reason are correct but Reason is not the correct explanation of the Assertion.
3 Assertion is correct but Reason is incorrect.
4 Assertion is incorrect but reason is correct.
PHXI07:SYSTEMS OF PARTICLES AND ROTATIONAL MOTION

365673 Assertion :
Moment of inertia is always constant.
Reason :
Angular momentum is conserved if the external torque is zero.

1 Both Assertion and Reason are correct and Reason is the correct explanation of the Assertion.
2 Both Assertion and Reason are correct but Reason is not the correct explanation of the Assertion.
3 Assertion is correct but Reason is incorrect.
4 Assertion is incorrect but reason is correct.
PHXI07:SYSTEMS OF PARTICLES AND ROTATIONAL MOTION

365674 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

1 \(1: 2\)
2 \(\sqrt{2: 1}\)
3 \(1: \sqrt{2}\)
4 \(2: 1\)
PHXI07:SYSTEMS OF PARTICLES AND ROTATIONAL MOTION

365675 A uniform rod \(AB\) mass \(m\) and length \(2 a\) is falling freely without rotation under gravity with \(A B\) horizontal. Suddenly the end \(A\) is fixed when the speed of the rod is \(v\). The angular speed with which the rod begins to rotate is

1 \(\dfrac{v}{3 a}\)
2 \(\dfrac{3 v}{4 a}\)
3 \(\dfrac{4 v}{3 a}\)
4 \(\dfrac{v}{2 a}\)
For More Updates join with Us
PHXI07:SYSTEMS OF PARTICLES AND ROTATIONAL MOTION

365671 A ballet dancer is rotating about his own vertical axis on smooth horizontal floor. \(I\), \(\omega ,L,K\) are moment of inertia, angular velocity, angular momentum, rotational kinetic energy of ballet dancer respectively. If ballet dancer stretches himself away from his axis of rotation then

1 \(I\) increases and \(\omega ,E\) decrease but \(L\) is constant
2 \(I\) decreases, \(\omega\) and \(E\) increase but \(L\) is constant
3 \(I\) increases, \(\omega\) decreases, \(L\) and \(E\) are constant
4 \(I\) increases, \(\omega\) increases but \(L\) and \(E\) are constant
PHXI07:SYSTEMS OF PARTICLES AND ROTATIONAL MOTION

365672 Assertion :
A person standing on a rotating platform suddenly stretched his arms, the platform slows down.
Reason :
A person by stretching his arms increase the moment of inertia and decreases angular velocity.

1 Both Assertion and Reason are correct and Reason is the correct explanation of the Assertion.
2 Both Assertion and Reason are correct but Reason is not the correct explanation of the Assertion.
3 Assertion is correct but Reason is incorrect.
4 Assertion is incorrect but reason is correct.
PHXI07:SYSTEMS OF PARTICLES AND ROTATIONAL MOTION

365673 Assertion :
Moment of inertia is always constant.
Reason :
Angular momentum is conserved if the external torque is zero.

1 Both Assertion and Reason are correct and Reason is the correct explanation of the Assertion.
2 Both Assertion and Reason are correct but Reason is not the correct explanation of the Assertion.
3 Assertion is correct but Reason is incorrect.
4 Assertion is incorrect but reason is correct.
PHXI07:SYSTEMS OF PARTICLES AND ROTATIONAL MOTION

365674 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

1 \(1: 2\)
2 \(\sqrt{2: 1}\)
3 \(1: \sqrt{2}\)
4 \(2: 1\)
PHXI07:SYSTEMS OF PARTICLES AND ROTATIONAL MOTION

365675 A uniform rod \(AB\) mass \(m\) and length \(2 a\) is falling freely without rotation under gravity with \(A B\) horizontal. Suddenly the end \(A\) is fixed when the speed of the rod is \(v\). The angular speed with which the rod begins to rotate is

1 \(\dfrac{v}{3 a}\)
2 \(\dfrac{3 v}{4 a}\)
3 \(\dfrac{4 v}{3 a}\)
4 \(\dfrac{v}{2 a}\)
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PHXI07:SYSTEMS OF PARTICLES AND ROTATIONAL MOTION

365671 A ballet dancer is rotating about his own vertical axis on smooth horizontal floor. \(I\), \(\omega ,L,K\) are moment of inertia, angular velocity, angular momentum, rotational kinetic energy of ballet dancer respectively. If ballet dancer stretches himself away from his axis of rotation then

1 \(I\) increases and \(\omega ,E\) decrease but \(L\) is constant
2 \(I\) decreases, \(\omega\) and \(E\) increase but \(L\) is constant
3 \(I\) increases, \(\omega\) decreases, \(L\) and \(E\) are constant
4 \(I\) increases, \(\omega\) increases but \(L\) and \(E\) are constant
PHXI07:SYSTEMS OF PARTICLES AND ROTATIONAL MOTION

365672 Assertion :
A person standing on a rotating platform suddenly stretched his arms, the platform slows down.
Reason :
A person by stretching his arms increase the moment of inertia and decreases angular velocity.

1 Both Assertion and Reason are correct and Reason is the correct explanation of the Assertion.
2 Both Assertion and Reason are correct but Reason is not the correct explanation of the Assertion.
3 Assertion is correct but Reason is incorrect.
4 Assertion is incorrect but reason is correct.
PHXI07:SYSTEMS OF PARTICLES AND ROTATIONAL MOTION

365673 Assertion :
Moment of inertia is always constant.
Reason :
Angular momentum is conserved if the external torque is zero.

1 Both Assertion and Reason are correct and Reason is the correct explanation of the Assertion.
2 Both Assertion and Reason are correct but Reason is not the correct explanation of the Assertion.
3 Assertion is correct but Reason is incorrect.
4 Assertion is incorrect but reason is correct.
PHXI07:SYSTEMS OF PARTICLES AND ROTATIONAL MOTION

365674 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

1 \(1: 2\)
2 \(\sqrt{2: 1}\)
3 \(1: \sqrt{2}\)
4 \(2: 1\)
PHXI07:SYSTEMS OF PARTICLES AND ROTATIONAL MOTION

365675 A uniform rod \(AB\) mass \(m\) and length \(2 a\) is falling freely without rotation under gravity with \(A B\) horizontal. Suddenly the end \(A\) is fixed when the speed of the rod is \(v\). The angular speed with which the rod begins to rotate is

1 \(\dfrac{v}{3 a}\)
2 \(\dfrac{3 v}{4 a}\)
3 \(\dfrac{4 v}{3 a}\)
4 \(\dfrac{v}{2 a}\)
Join With Us for More Updates
PHXI07:SYSTEMS OF PARTICLES AND ROTATIONAL MOTION

365671 A ballet dancer is rotating about his own vertical axis on smooth horizontal floor. \(I\), \(\omega ,L,K\) are moment of inertia, angular velocity, angular momentum, rotational kinetic energy of ballet dancer respectively. If ballet dancer stretches himself away from his axis of rotation then

1 \(I\) increases and \(\omega ,E\) decrease but \(L\) is constant
2 \(I\) decreases, \(\omega\) and \(E\) increase but \(L\) is constant
3 \(I\) increases, \(\omega\) decreases, \(L\) and \(E\) are constant
4 \(I\) increases, \(\omega\) increases but \(L\) and \(E\) are constant
PHXI07:SYSTEMS OF PARTICLES AND ROTATIONAL MOTION

365672 Assertion :
A person standing on a rotating platform suddenly stretched his arms, the platform slows down.
Reason :
A person by stretching his arms increase the moment of inertia and decreases angular velocity.

1 Both Assertion and Reason are correct and Reason is the correct explanation of the Assertion.
2 Both Assertion and Reason are correct but Reason is not the correct explanation of the Assertion.
3 Assertion is correct but Reason is incorrect.
4 Assertion is incorrect but reason is correct.
PHXI07:SYSTEMS OF PARTICLES AND ROTATIONAL MOTION

365673 Assertion :
Moment of inertia is always constant.
Reason :
Angular momentum is conserved if the external torque is zero.

1 Both Assertion and Reason are correct and Reason is the correct explanation of the Assertion.
2 Both Assertion and Reason are correct but Reason is not the correct explanation of the Assertion.
3 Assertion is correct but Reason is incorrect.
4 Assertion is incorrect but reason is correct.
PHXI07:SYSTEMS OF PARTICLES AND ROTATIONAL MOTION

365674 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

1 \(1: 2\)
2 \(\sqrt{2: 1}\)
3 \(1: \sqrt{2}\)
4 \(2: 1\)
PHXI07:SYSTEMS OF PARTICLES AND ROTATIONAL MOTION

365675 A uniform rod \(AB\) mass \(m\) and length \(2 a\) is falling freely without rotation under gravity with \(A B\) horizontal. Suddenly the end \(A\) is fixed when the speed of the rod is \(v\). The angular speed with which the rod begins to rotate is

1 \(\dfrac{v}{3 a}\)
2 \(\dfrac{3 v}{4 a}\)
3 \(\dfrac{4 v}{3 a}\)
4 \(\dfrac{v}{2 a}\)