Chapter 28, Problem 4A

To determine

To explain: The effect on the light of a certain frequency that encounters atoms of the same resonant frequency.

Explanation of Solution

Introduction:

When natural vibration frequency is equal to the resonant frequency then light is absorbed.

The amplitude of the oscillations are large at the resonant frequency. So, when the vibrating frequency of the light is matched with the resonant frequency then the light is absorbed. But the light is re-emitted at the frequencies below the resonant frequency.

Conclusion:

Therefore, at the resonant frequency the light is absorbed.