Question

A particle of mass $M$ is moving in a horizontal circle of radius $R$ with uniform speed $V$. When it moves from one point to a diametrically opposite point, its

• A. Kinetic energy changes by $\frac{M{V}^2}{4}$
• B. momentum does not change.
• C. Momentum changes by $2MV$.
• D. Kinetic energy changes by $M{V}^2$

Answer 1

The correct option is C Momentum changes by $2MV$.

On the diametrically opposite points, the velocities have same magnitude, but opposite directions, Therefore, change in momentum is $MV-(-MV)=2MV$. Hence, the correct answer is option (C).