Question

A particle is moving in a circle of radius $r$ having centre at $O$, with a constant speed $v$. The magnitude of change in velocity in moving from $A$ to $B$ is

• A. $2 v$
• B. $0$
• C. $\sqrt{3} v$
• D. $v$

Answer 1

Answer: (D)

$[\Delta \vec{V}]=2 V \sin \frac{\theta}{2}$
$=2 \times V \times \sin \left(\frac{60^{\circ}}{2}\right)$
$=2 \times V \times \frac{1}{2}$
$\Rightarrow V=|\Delta \vec{V}|$