Assume a bulb of efficiency $2.5\%$ as a point source. The peak values of electric field produced by the radiation coming from a $100\, W$ bulb at a distance of $3\, m$ is respectively.....$V\,{m^{ - 1}}$

  • A

    $2.5$

  • B

    $4.2$

  • C

    $4.08$

  • D

    $3.6$

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