(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A flashlight is shining into a box. There are no reflections. We know the power of the flashlight in Watts. We know the volume of the box.

Question: How much energy (associated with the EM field) is in the box?

2. Relevant equations

3. The attempt at a solution

Integrate the power density (J s^-1 m^-3) over the volume of the box. But what is the power density?

Hints would be preferred over full solutions :)

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# Light in a Box

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