Question

The mass of the earth is $6\times {10}^{24}$ kg and that of the moon is $7.4\times {10}^{22}$ kg. If the distance between the earth and the moon is 3.8$\times {10}^5$ km. calculate the force exerted by the earth.

Answer 1

$F=\frac{G{M}_e{M}_m}{R^2}$

$⟹F=\frac{6.67\times {10}^{-11}\times 6\times {10}^{24}\times 7.4\times {10}^{22}}{(3.8\times {10}^8{)}^2}$

$⟹F=2.05\times {10}^{20}N$