Malus's Law
Calculate Malus's Law instantly with the exact formula and a worked example. Free online calculator — no signup, works on mobile.
Malus's Law
I₀
Angle, °
I = I₀·cos²θ
75
More about: Malus's Law
What it calculates
The “Malus's Law” calculator computes I = I₀·cos²θ from 2 parameters: i₀, angle, °.
A standard physics formula used in educational and engineering tasks.
Example calculation
With parameters I₀ = 100, Angle, ° = 30 the result is 75.
How to use
- Enter the parameter values — every field above is adjustable with a slider.
- The result and related metrics are calculated automatically as you type.
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