The electric field of a plane electromagnetic wave varies with time of amplitude 2 Vm-1 propagating along z-axis. The average energy density of the magnetic field is (in Jm−3 ) |
13.29 × 10−12 8.86 × 10-12 17.72 × 10-12 4.43 × 10-12 |
8.86 × 10-12 |
$ U=\frac{1}{2}×\frac{1}{2}ε_0E^2 = \frac{1}{2}×\frac{1}{2}×8.85 ×10^{-12} ×(2)^2$ $= 8.85 × 10^{-12} Jm^{-3}$ |