An object weighs $10 \, N$ in air. When immersed fully in water,it weighs only $8 \, N$. The weight of the liquid displaced by the object will be (in $, N$)

What is the acceleration due to gravity at the centre of the earth (in $m/s^2$)?

The force of attraction between two unit point masses separated by a unit distance is called

The equation $F = G \frac{m_1 m_2}{r^2}$ is valid only for:

State the universal law of gravitation.

$A$ boy on a cliff $49\, m$ high drops a stone. One second later,he throws a second stone after the first. They both hit the ground at the same time. With what speed did he throw the second stone?