Two point masses $m$ and $4m$ are separated by a distance $d$ on a line. $A$ third point mass $m_0$ is to be placed at a point on the line such that the net gravitational force on it is zero. The distance of that point from the $m$ mass is:

Three particles each of mass $m_{1}$ are placed at the corners of an equilateral triangle of side $\frac{L}{3}$. $A$ particle of mass $m_{2}$ is placed at the midpoint of any one side of the triangle. Due to the system of particles,the net gravitational force acting on $m_{2}$ is ($G$ = Universal constant of gravitation).

Find the gravitational force between two stones, each of mass $2 \,kg$ and separated by a distance $1 \,m$ in vacuum.

The distance between two objects $A$ and $B$ is $r$. The gravitational force between them is inversely proportional to the square of the distance. If the gravitational force between these two objects were inversely proportional to the fourth power of the distance,find the acceleration of object $A$.

The $SI$ unit of $\frac{G}{g}$ is $(g = \text{acceleration due to gravity}, G = \text{gravitational constant})$

The tidal waves in the sea are primarily due to