A particle is moving in a circle with uniform speed ' $v$ '. In moving from a point to another diametrically…

A particle is moving in a circle with uniform speed ' $v$ '. In moving from a point to another diametrically opposite point
  1. the momentum changes by $\mathrm{mv}$
  2. the momentum changes by $2 \mathrm{mv}$
  3. the kinetic energy changes by $\frac{1}{2} \mathrm{mv}^2$
  4. the kinetic energy changes by $\mathrm{mv}^2$

Solution

At both points, the momentum will be mv, but will be in opposite directions. $\begin{array}{ll} \therefore & \Delta \mathrm{P}=\mathrm{mv}-(-\mathrm{mv}) \\ \therefore & \Delta \mathrm{P}=2 \mathrm{mv} \end{array}$ The momentum changes by $2 \mathrm{mv}$. /

Asked in: MHT CET 2023 (12 May Shift 2)

Practice more Motion In Two Dimensions questions on Aicharya