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 $2MV$

Velocity at initial point$=V$
Velocity at point diametrically opposite to initial point$=-V$
Thus, change in momentum$=MV-(-MV)=2MV$