A body weight $W$, is projected vertically upwards from earth's surface to reach a height above the earth which is equal to nine times the radius of earth. The weight of the body at that height will be

Two masses $m_1$ and $m_2\, (m_1 < m_2)$ are released from rest from a finite distance. They start under their mutual gravitational attraction

The acceleration due to gravity on the surface of earth is $g$. If the diameter of earth reduces to half of its original value and mass remains constant, then acceleration due to gravity on the surface of earth would be :

Two planets $A$ and $B$ of radii $R$ and $1.5 R$ have densities $\rho$ and $\rho / 2$ respectively. The ratio of acceleration due to gravity at the surface of $B$ to $A$ is :

If mass of earth decreases by $25 \%$ and its radius increases by $50 \%$, then acceleration due to gravity at its surface decreases by nearly ......... $\%$

The mass of moon is $7.34 \times {10^{22}}\,kg$ and radius of moon is $1.74 \times {10^6}\,m$ then The value of gravitation accelaration will be ....... $N/kg$