Question

If potential energy of a body of mass m on the surface of earth is taken as zero then its potential energy at height h above the surface of earth is (R is radius of earth and M is the mass of earth)
a)-GMm/(R+h)
b)-GMm/(h)
c)GMmh/R(R+h)
d)GMmh/(h+2R)

Answer 1

Answer:

c)GMmh/R(R+h)

Explanation:

Mass of body = m (Given)

Height of body = h Given)

Radius of the earth = R Given)

Mass of the earth = M Given)

The total potential energy of an object is the amount of work required to get it from an infinite distance to its position.  It's gravitational energy potential is the contribution to the total energy potential due to the gravity effect.  Potential energy can also exist because of the other three fundamental forces.

Therefore,

The gravitational potential energy at height h will be -

U =−GMm/R+h + GMm/R

= GMmh/R(R+h)

Thus, potential energy will be GMmh/R(R+h).