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

  • A
    $2.5$
  • B
    $4.2$
  • C
    $4.08$
  • D
    $3.6$

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