In an electromagnetic wave, the amplitude of electric field is \(1V/m\), the frequency wave is \(5 \times 10^{14} Hz\). The wave is propagating along \(z\)-axis. The average energy density of electric field, in Joule/m, will be
1
\(1.1 \times 10^{-11}\)
2
\(2.2 \times 10^{-12}\)
3
\(3.3 \times 10^{-13}\)
4
\(4.4 \times 10^{-14}\)