Chapter 42, Problem 19SP

To determine

The change in energy of the photon if its frequency is doubled.

Answer to Problem 19SP

Solution:

Theenergy will be doubled.

Explanation of Solution

Given data:

The frequency of the photon is doubled.

Formula used:

Write the expression for the energy of a photon:

$E=hf$

Here, $h$ is Plank’s constant and $f$ is frequency of the photon.

Explanation:

Recall the expression for the energy of a photon:

$E=hf$

Consider it as the initial energy of the photon:

As the frequency of the photon is doubled, change the value of frequency to $2f$.

Therefore, the updated energy of the photon is

$E^{\prime }=h\left(2f\right)$

Compare the initial and final energy of the photon:

$E^{\prime }=2E$

Conclusion:

The energy of the photon is doubled.