Question

Find the gravitational attraction between two atoms in a hydrogen molecule when $G$ is $6.67\times {10}^{-11}N{m}^2{kg}^{-2}$, mass of a hydrogen atom is $1.67\times {10}^{-27}kg$ and the distance between two atoms is $1\mathring{A}$.

• A. $11.14\times {10}^{-18}N$
• B. $2.39\times {10}^{-45}N$
• C. $1.86\times {10}^{-44}N$
• D. $4.18\times {10}^{-23}N$

Answer 1

The correct option is C $1.86\times {10}^{-44}N$

We know from Newton's law of gravitation that the gravitational attraction between two masses is $F=\frac{{GM}_1{M}_2}{R^2}$, where $M_1$, $M_2$ are the masses and $R$ is the distance between the masses.

Given:

$G={6.67\times 10}^{-11}N{m}^2{kg}^{-2}{M}_1=M_2=1.67\times {10}^{-27}kgR=1\stackrel{\circ }{A}={10}^{-10}m\therefore F=\frac{6.67\times {10}^{-11}\times 1.67\times 1.67\times {10}^{-27-27}}{{10}^{-10}\times {10}^{-10}}=1.86\times {10}^{-44}N$