The amplitude of electric field at a distance `r` from a point source of power `P` is (taking 100% efficiency).

If the amplitude of a wave at a distance r from a point source is A , the amplitude at a distance 2 r will be

A point source of electromagnetic radiation has an average power output of 800W . The maximum value of electric field at a distance 3.5m from the source will be 62.6 V/m , the energy density at a distance 3.5 m from the source will be- (in "joule"//m^(3) )

If the amplitude of waves at a distance r from line source is A . The amplitude at a distance 4r will be

The electric field at a point at a distance r from an electric dipole is proportional to ......

A point source of electromagnetic radiation has an average power output of 800W. The mximum value of electric field at a distance 3.5 m from the source will be 62.6 V/m, the maximum value of magnetic field will be -