Q. Figure shows a body of mass $m$ moving with a uniform speed $v$ along a circle of radius $r$. The change in velocity in going from $A\ $to $B$ is
A) $v\sqrt{2}$
B) $v/\sqrt{2}$
C) $v$
D) zero
Explanation
(a) $\left| \overrightarrow{\mathrm{\Delta}v} \right| = 2v\sin{(\theta/2)} = 2v\sin\left( \frac{90}{2} \right) = 2v\sin 45 = v\sqrt{2}$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.