According to the universal law of gravitation, gravitational force (\(F\)) acting between two objects is inversely proportional to the square of the distance (\(r\)) between them, i.e.,
\(๐นโ \frac{1 }{๐^2 }\)
If distance r becomes \(\frac{r}2\), then the gravitational force will be proportional to
\(\frac1{ (\frac๐{2})^2}\) = \(\frac4{๐^2}\)
Hence, if the distance is reduced to half, then the gravitational force becomes four times larger than the previous value.
A small point of mass \(m\) is placed at a distance \(2R\) from the center \(O\) of a big uniform solid sphere of mass \(M\) and radius \(R\). The gravitational force on \(m\) due to \(M\) is \(F_1\). A spherical part of radius \(R/3\) is removed from the big sphere as shown in the figure, and the gravitational force on \(m\) due to the remaining part of \(M\) is found to be \(F_2\). The value of the ratio \( F_1 : F_2 \) is: