What is gravitation?

A body weight 63 N on the surface of the earth. What is the gravitational force on it due to the earth at a height equal to half the radius of earth ?

A body weights 63 N on the surface of the earth. What is the gravitational force on it due to the earth at a height equal to the half the radius of the earth?

A man of mass 70 kg is sitting in a motor car. The car is moving with an acceleration of 5 m cdot s^(-2) . What is the gravitational force on the man? [ g = 9.8 m cdot s^(-2) ]

The radius of the earth is 6.38 xx10^8 cm. its mean density is 5.5 g*cm ^(-3) and the universal gravitational constant is 6.67xx10^(-8) CGS unit. What is the gravitational potential at any point on the earth's surface ?

Two piece of iron are kept at a distance of 20 cm. The mass of each of the piece is 100 kg. What is the gravitational force acting between them ? Given , g=6.67xx10^(-11) N*m^2*kg^(-2) .

Two heavy spheres each of mass 100 kg and radius 0.10 m are placed 1.0 m apart on a horizontal table. What is the gravitational force and potential at the mid-point of the line joining the centres of the spheres ? Is an object placed at that point in equilibrium ? if so, is the equilibrium stable or unstable ?

Show that the gravitational potential at a point, distance r from the mass M is given by V =-(GM/r)