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Concepts Of Physics MCQ Edition [Volume 1]

Exam: Concepts Of Physics MCQ Edition [Volume 1]
Subject: Physics
Chapter: Rotational Mechanics

Concepts Of Physics MCQ Edition [Volume 1] · Physics · Rotational Mechanics

A kid of mass M stands at the edge of a platform of radius R which...

A kid of mass

M

stands at the edge of a platform of radius

R

which can rotate freely about its axis. The moment of inertia of the platform is

I

. The system is initially at rest, and the kid holds a ball of mass

m

while standing on the rim. He throws the ball horizontally, tangential to the rim, with speed

v

as seen by his friend. Find the angular velocity with which the platform starts rotating.

Options

A $\dfrac{mvR}{I + MR^2}$
B $\dfrac{mvR}{I}$
C $\dfrac{m v}{I + MR^2}$
D $\dfrac{mvR}{I + (M + m)R^2}$

Correct answer

A. $\dfrac{mvR}{I + MR^2}$

Step-by-step solution

\dfrac{mvR}{I + MR^2}

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