Chapter 28, Problem 54A

To determine

Whether photons emitted by the mercury atom after emission of visible photon would be visible or not.

Explanation of Solution

Introduction:

Photons of wavelength between $400\text{ nm to 700 nm}$ are only visible.

Only photons of wavelength between $400\text{ nm to 700 nm}$ are visible. The photons emitted after emission of visible photons have wavelength below the range of visible spectrum as they are emitted from a lower energy level to the ground state and hence are in the infrared region and so, not visible.

Conclusion:

Photons emitted by the mercury atom, until it reaches the ground state, after emission of visible photon will not be visible.