Question

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

Answer 1

The correct option is C $n_r>n_b$

As per the question, $n_r\times \frac{hc}{{\lambda }_r}=n_b\times \frac{hc}{{\lambda }_b}\Rightarrow \frac{n_r}{n_b}=\frac{{\lambda }_r}{{\lambda }_b}>1$