Question

two objects, one with a mass of 10kg and the other with a mass of 1.5×10^5 kg are sitting with their centers 20m apart. what is their gravitational force on each other?

Explanation:

Step1: Identify the formula

Newton's law of universal gravitation: $F = G\frac{m_1m_2}{r^2}$, where $G = 6.67\times10^{- 11}\ N\cdot m^{2}/kg^{2}$, $m_1 = 10\ kg$, $m_2=1.5\times10^{5}\ kg$, $r = 20\ m$.

Step2: Substitute the values into the formula

$$\begin{align*} F&=(6.67\times 10^{-11})\frac{10\times1.5\times 10^{5}}{20^{2}}\\ &=(6.67\times 10^{-11})\frac{1.5\times 10^{6}}{400}\\ &=(6.67\times 10^{-11})\times3750\\ &=2.50125\times10^{-7}\ N \end{align*}$$

Answer:

$2.5\times 10^{-7}\ N$