Question

Calculate the gravitational force between two objects when they are 0.630m apart. Each object has a mass of 7.00kg. 

Answer 1

Given:

$m_1=m_2=\rm 7.00\:\rm kg$

$r=0.630\:\rm m$

The law of universal gravitation says

$$F=G\frac{m_1m_2}{r^2}=6.67*10^{-11}\frac{7.00*7.00}{0.630^2}=8.23*10^{-9}\:\rm N$$