A bulb emits light of wavelength $4500\;A$ . The bulb is rated as $150\;walt$ and $8\%$ of the energy is emitted as light. How many photons are emitted by the bulb per second .

Question

$\begin{array}{1 1} (a)\; 2.715 \times 10^{19} \\(b)\; 1.715 \times 10^{19} \\ (c)\; 3.715 \times 10^{19} \\ (d)\; 4.715 \times 10^{19} \end{array}$