Short-answer questions

PHYSICS · Multi-part · CBSE · Physics · Gravitation · Gravitation

Problem

Short-answer questions (1) State Newton's universal law of gravitation. (2) Show that the gravitational potential energy of a body of mass

m

, at the surface of the Earth of radius

R

and mass

M

, is given by

E_P=-\frac{GMm}{R}

. (3) Hence, show that the gravitational potential at the Earth's surface is

-62.5\text{ MJ kg}^{-1}

. Given

M_{\text{Earth}}=6\times10^{24}\text{ kg}

R=6.4\times10^6\text{ m}

, and

G=6.67\times10^{-11}\text{ N m}^2\text{ kg}^{-2}