Q. A satellite is moving around the earth with speed $v$ in a circular orbit of radius $r$. If the orbit radius is decreased by 1%, its speed will
A) Increase by 1%
B) Increase by 0.5%
C) Decrease by 1%
D) Decrease by 0.5%
Explanation
(b) $v \propto \frac{1}{\sqrt{r}}$
% increase in speed $= 1/2$ (% decrease in radius)
$= 1/2(1\%) = 0.5\%$
$i.e.$ speed will increase by 0.5%
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.