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

A low energy, 13-watt bulb illuminates your desk from a distance of 1.2m. You can assume that it acts as a point source and that it is 100% efficient. What is the intensity (power per unit area) at the desk (in Wmˉ²)?

2. Relevant equations

Velocity = Frequency * Wavelength

Intensity is proportional to amplilude²

3. The attempt at a solution

I don't know how to start!

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# Homework Help: Intensity question

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