A sphere of mass `40 kg` is attracted by a second sphere of mass `15 kg`, when their centres are `20 cm` apart, with a force of `0.1` miligram weight. Caculate the value of gravitational constant.

Explanation

Here, `m_(1) = 40 kg`,`m_(2) = 15 kg`, `r = 0.20 m`,
`F = 0.1` milligram wt. `= 0.1 xx 10^(-6) kg wt. = 0.1 xx 10^(-6) xx 9.8 N`
Now, `G = (Fr^(2))/(m_(1)m_(2)) = ((0.1 xx 10^(-6) xx 9.8)xx(0.20)^(2))/(40xx 15) = 6.53 xx 10^(-11) Nm^(2) kg^(-2)`