Question

A small block of superdense material has a mass of 3 x 10 ²⁴ kg. It is situated at a height h (much smaller than the earth's radius) from where it falls on the earth's surface. Find its speed when its height from the earth's surface has reduced to h /2. The mass of the earth is 6 x 10 ²⁴ kg.

Answer 1

The two blocks are attracted by gravitational force of attraction. The gravitation potential energy stored will be the K.E. of two blocks.

As h < < < R, if can be neglected