A radio station on the surface of the earth radiates 50 kW . If transmitter radiates equally in all directions avove the surface of the earth . Find the amplitude of electric field detected 100 km away :

A point source of 2 watt is radiating uniformly in all direction in vacuum. Find the amplitude of electric field at a distance 2m from it-

An artificial satellite is moving in an orbit around the earth with a velocity equal to one-third the escape velocity from the surface of the earth. (ii) The satellite comes to rest in its orbit and then is allowed to fall freely on to the surface of the earth. Find the speed with which the satellite strikes the earth's surface. Given radius of earth =6400 km.

The electric field near the surface of the earth is 300V//m . The surface density of charge on the earth's surface is

If the weight of a body is 100 N, on the surface of the earth then its binding energy on the surface of the earth is, (R_(E)=6400km)

At what height above the surface of earth acceleration due to gravity will be (ii) 50% of its value on the surface of the earth. Given radius of earth =6400 km.