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Focal Length and Radius

f = \frac{R}{2}

f = R/2

The focal length of a spherical mirror is half its radius of curvature.

Variables

f

Focal length

m

R

Radius of curvature

m

Your notes

0/5000

Calculator

Solves for f - Focal length (m)

Rm

Enter R to calculate f.

Related formulas

\frac{1}{f}Mirror EquationReflection

Tags

focal length mirrors curvature

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