Question

A satellite is revolving around Earth in a circular orbit of radius equal to the diameter of Earth. The minimum % increase in the speed of that satellite so that it escapes from Earth's gravity is

• A. 100 %
• B. 82.8 %
• C. 50 %
• D. 41.4 %

Answer 1

The correct option is A 100 %

$V_o=\sqrt{\frac{GM}{2R}}$

$V_e=\sqrt{\frac{2GM}{R}}$

Percentage change $=\frac{V_e-V_o}{V_o}\times 100$$=\frac{\sqrt{2}-\frac{1}{\sqrt{2}}}{\frac{1}{\sqrt{2}}}\times 100$$=100$ %