Practicing Success
A point source of Electromagnetic radiation has an average power output of 1500 W. The maximum value of electric field at a distance of 3 m from this source in Vm-1 is |
500 73 $\frac{500}{3}$ $\frac{250}{3}$ |
73 |
Intensity $ I = \frac{pressure}{area}=\frac{p}{4\pi r^2}$ =average energy density × velocity $=\frac{1}{2}ε_0E^2_0c$ $∴ E_0 = \sqrt{\frac{P}{4\pi ε_0r^2c}}=\sqrt{\frac{P}{2\pi ε_0r^2c}}$ here r = 3m , P = 1500 W $E_0 = 73V/m$ |