Easy MCQ +4 / -1 PYQ · JEE Mains 2024

Two sources of light emit with a power of $200 \mathrm{~W}$. The ratio of number of photons of visible light emitted by each source having wavelengths $300 \mathrm{~nm}$ and $500 \mathrm{~nm}$ respectively, will be :

  1. A $5: 3$
  2. B $3: 5$ Correct answer
  3. C $1: 5$
  4. D $1: 3$

Solution

<p>$$\begin{aligned} & \mathrm{n}_1 \times \frac{\mathrm{hc}}{\lambda_1}=200 \\ & \mathrm{n}_2 \times \frac{\mathrm{hc}}{\lambda_2}=200 \\ & \frac{\mathrm{n}_1}{\mathrm{n}_2}=\frac{\lambda_1}{\lambda_2}=\frac{300}{500} \\ & \frac{\mathrm{n}_1}{\mathrm{n}_2}=\frac{3}{5} \end{aligned}$$</p>

About this question

Subject: Physics · Chapter: Dual Nature of Matter and Radiation · Topic: Photoelectric Effect

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