Question

Given mass of earth =$6.4\times {10}^{24}$ kg , radius of earth = $6.4\times {10}^6$ m. Calculate the force of attraction experienced by a man of mass 50 kg.

Answer 1

Force of gravitation is given by the expression,

$F=\frac{G{m}_1{m}_2}{r^2}$

Here, mass of earth, $m_1$ = $6\times {10}^{24}$ kg;

mass of man, $m_2$ = 50 kg

Distance between them is to be taken equal to the radius of the earth.

r = $6.4\times {10}^6$ m

Substituting these values, we get

$F=\frac{6.67\times {10}^{-11}\times 50\times 6\times {10}^{24}}{(6.4\times {10}^6{)}^2}$ = 488.5 N.