Question

A body (mass $m$) starts its motion from rest from a point distant $R_0$ ($R_0>R$) from the centre of the earth. The velocity acquired by the body when it reaches the surface of earth will be ($G =$ universal constant of gravitation, $M =$ mass of earth, $R =$ radius of earth)}

• A. 2GM \left( \frac{1}{R} - \frac{1}{R_0} \right)
• B. \left[ 2GM \left( \frac{1}{R} - \frac{1}{R_0} \right) \right]^{\frac{1}{2
• C. GM \left( \frac{1}{R} - \frac{1}{R_0} \right)
• D. 2GM \left[ \left( \frac{1}{R} - \frac{1}{R_0} \right) \right]^{\frac{1}{2

Hint:

In central force fields like gravity, loss in Potential Energy equals gain in Kinetic Energy.

Answer 1

The Correct Option is A