The factors associated with the motion of an object are: Force,Velocity,Acceleration,and Momentum. Out of these four factors,which one remains constant for all bodies—large or small—undergoing a free fall?

Write True or False for the following statement:
The value of $G$ is high if the radius of the body is more and less if radius is less.

When an object, say an apple, falls towards the Earth, the Earth rises up to meet it. Is this true? If so, why is the Earth's motion not noticeable?

$A$ stone is dropped from a height of $20\, m$.
$(a)$ How long will it take to reach the ground?
$(b)$ What will be its speed when it hits the ground? $(g=10\, m s^{-2})$

The mass of a girl is $50\, kg$. What will be her approximate weight on the Earth? How will her mass and weight change on the surface of the Moon?

$(i)$ How is the force of attraction dependent on the masses of objects and the distance between them?
$(ii)$ The mass of the Earth is $6 \times 10^{24} \, kg$ and that of a natural satellite is $6.5 \times 10^{20} \, kg$. If the distance between them is $3.35 \times 10^{6} \, km$, calculate the force exerted by the Earth on it. $(G = 6.7 \times 10^{-11} \, Nm^{2} kg^{-2})$