Assertion (A): A person standing on a rotating platform suddenly stretched his arms, the platform slows down.

Reason (R): A person by stretching his arms increases the moment of inertia and decreases angular velocity.

In each of the following questions, a statement of Assertion is given followed by a corresponding statement of Reason just below it. Of the statements, mark the correct answer as-

Assertion (A): If a particle moves with a constant velocity then angular momentum of this particle about any point remains constant.

Reason (R): Angular momentum has the units of Planck's constant.

Codes:

In each of the following questions, a statement of Assertion is given followed by a corresponding statement of Reason just below it. Of the statements, mark the correct answer as-

Assertion (A): When a ball collides elastically with a floor, it rebounds with the same velocity as with it strikes.

Reason (R): Momentum of earth and ball system remains constant.

Codes:

In each of the following questions, a statement of Assertion is given followed by a corresponding statement of Reason just below it. Of the statements, mark the correct answer as-

Assertion (A): A small force can affect on same as large force.

Reason (R): The moment of a force is the product of force and its perpendicular distance from the axis of rotation.

Codes:

Consider the following statements:

I. A body having constant linear velocity may have some angular speed with respect to a point.

II. A force passing through the centre of rotation can produce moment to a body.

III. Torque has the SI unit N-m.

IV. Centre of gravity is point where entire mass of the body is assumed to be concentrated.

Which one of the following options are correct?

If ${\mathrm{I}}_{\mathrm{A}}$ and ${\mathrm{I}}_{\mathrm{B}}$ are the moments of inertia of a body about two axes $\mathrm{A}$ and $\mathrm{B}$ respectively. The axis $\mathrm{A}$ passes through the centre of mass of the body but $\mathrm{B}$ does not. Consider the following given below

I. ${\mathrm{I}}_{\mathrm{A}}<{\mathrm{I}}_{\mathrm{B}}$.

II. If ${\mathrm{I}}_{\mathrm{A}}<{\mathrm{I}}_{\mathrm{B}}$, the axes are parallel.

III. If the axes are parallel, ${\mathrm{I}}_{\mathrm{A}}<{\mathrm{I}}_{\mathrm{B}}$.

IV. If the axes are not parallel, ${\mathrm{I}}_{\mathrm{A}}\ge {\mathrm{I}}_{\mathrm{B}}$.

Which one of the following options is/are correct?