In an electromagnetic wave, the amplitude of electric field is $1 V/m.$  the frequency of wave is $5 \times {10^{14}}\,Hz$. The wave is propagating along $z-$ axis. The average energy density of electric field, in $Joule/m^3$, will be

  • A

    $1.1 \times {10^{ - 11}}$

  • B

    $2.2 \times {10^{ - 12}}$

  • C

    $3.3 \times {10^{ - 13}}$

  • D

    $4.4 \times {10^{ - 14}}$

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