Give an example of the motion of an object under the influence of gravitational force on Earth.

State whether the following statement is True or False:
The centre of mass and centre of gravity for a small body lie at the same point.

Three students $A, B$ and $C$ were performing an experiment to establish the relation between the weight of a wooden block and the minimum force required to just move it on a horizontal surface. The experimental setup used by each is as shown in the figures given below.
The result obtained by them will be:

Where will a body weigh more: $1 \, km$ above the surface of the earth or $1 \, km$ below the surface of the earth?

How does acceleration due to gravity depend on the mass of the planet?

State the source of centripetal force that our earth requires to revolve around the sun. List the factors on which this force depends.