Q. An artificial satellite is revolving round the earth in a circular orbit. Its velocity is half the escape velocity. Its height from earth’s surface is
A) $6400\ km$
B) $12800\ km$
C) $3200\ km$
D) $1600\ km$
Explanation
(a) $v = \sqrt{\frac{GM}{R + h}} = \frac{1}{2}\sqrt{\frac{2GM}{R}}$
$\Rightarrow 4R = 2(R + h) \Rightarrow h = R = 6400\ km$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.