## Intensity

$c=\lambda v$

Rebecca Doan 2L
Posts: 51
Joined: Thu Jul 27, 2017 3:01 am

### Intensity

What is meant by the intensity of a wave or the intensity of the light?

Chem_Mod
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### Re: Intensity

Intensity of light is simply the number of photons, however as we know the number of photons is not as relevant as each photons wavelength/frequency/energy while doing photoelectric effect problems.

Michelle Lee 2E
Posts: 64
Joined: Thu Jul 27, 2017 3:01 am

### Re: Intensity

How do we measure intensity? In the book on page 4, it says intensity is the square of the altitude. However, the above response defines intensity as the number of photons. Then on page 9, the Stefan-Boltzmann law is explained. How am I supposed to relate all this information?

Sophia Bozone 2G
Posts: 51
Joined: Fri Sep 29, 2017 7:07 am

### Re: Intensity

In typical waves, intensity is measured as an increase in amplitude. Amplitude is the height of the waves, or the distance of the crests and troughs of waves from the midpoint or node. However, because light functions as a wave and proton, the amplitude does nothing to increase the amount of energy that the photon is carrying because it transfers energy in quanta.