Q: Let n_{r} and n_{b} be respectively the number of photons emitted by a red bulb and a blue bulb of equal power in a given time.

(A) n_{r} = n_{b}

(B) n_{r} < n_{b}

(C) n_{r} > n_{b}

(D) data insufficient

**Solution :** $\large E = \frac{12400}{\lambda (A^o)}$

Number of Photon $\large N = \frac{P}{E} = \frac{P}{hc/\lambda}$

$\large N = \frac{P \lambda}{h c} $

$\large N \propto \lambda $

Correct option is (C)