Question

A particle is moving along a circular path of radius 2 m with uniform speed of 5 $m{s}^{-1}$. What will be the change in velocity when the particle completes half of the revolution?

• A. Zero
• B. 10 $m{s}^{-1}$
• C. $10\sqrt{2}m{s}^{-1}$
• D. $\frac{10}{\sqrt{2}}m{s}^{-1}$

Answer 1

Answer: (B)

10 $m{s}^{-1}$

$\begin{array}{c}\text{Given,}R=2m\text{,}\\ \begin{array}{cc}& {\overrightarrow{V}}_A=\left(5\hat{i}\right)m/s\\ & \text{ard,}{\overrightarrow{V}}_B=-\left(5\hat{i}\right)m/s.\end{array}\end{array}$

$\begin{array}{cc}\text{Thus, change in velecity}& =\overrightarrow{V_B}-{\overrightarrow{V}}_A\\ & =-10\hat{i}\end{array}$

$\text{Hence, magnitude}=10m/s$