Optics & Waves
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Malus's Law

Intensity of polarised light through a polariser.

Formula

I=I0cos⁡2θI = I_0\cos^2\theta

Variables

I_0Incident intensity
\thetaAngle

Did You Know?

Polarised sunglasses use Malus's law to block glare by filtering out horizontally vibrating light.

polarisationmalusoptics