A body of mass m is situated at a distance 4R above the earth's surface, where R is the radius of earth. How much minimum energy be given to the body so that it may escape

Q. A uniform chain of mass '

m

' is placed over half ring. If the length of the chain is

π R

, then find potential energy of the chain.

Join BYJU'S Learning Program

The potential energy of a satellite of mass m revolving at height R above the surface of the earth where R= radius of earth is

The correct option is B −mgR2PE=−GMm2R−(−GMmR)=−GMm2RAlso, g=GMR2Putting the value of GMR in equation (1) we get,PE=−gmR2

The potential energy of a satellite of mass $m$ revolving at height $R$ above the surface of the earth where $R =$ radius of earth is

The correct option is B $- \frac{m g R}{2}$
$P E = \frac{- G M m}{2 R} - (\frac{- G M m}{R}) = \frac{- G M m}{2 R}$
Also,
$g = \frac{G M}{R^{2}}$
Putting the value of $\frac{G M}{R}$ in equation $(1)$ we get,
$P E = \frac{- g m R}{2}$