Question

Q13. The gravitational force between two masses m1 and m2 separated
by a distance r in the air is F. What is the gravitational force between
these masses separated by the same distance r in a vacuum?

Please help me​

Answer 1

Explanation:

Gravitational force doesn't depends on media (and if depends, it's so small that it can be neglected.)

Hence, the force of gravitation experienced in air will be equivalent to that of in vacuum (it varies to a small magnitude so it can be neglected).

So, the force of gravitation in air or $F_{a}$  will be;

                   = $F_{a}$ ∝ $m_{1}m_{2}$;

                   = $F_{a}$ ∝ $\frac{1}{r^{2}}$;

                   = $F_{a}$ ∝ $\frac{m_{1}m_{2} }{r^{2} }$;

                   = $F_{a}$= G  $\frac{m_{1}m_{2} }{r^{2} }$;

Hence, $F_{a}$ = $F_{0}$         (here, $F_{0}$  is the force of gravitation in vacuum.)

That's all.