An object is placed at 25 cm from a convex mirror. Its image is formed 15 cm from the mirror. Find the focal length of the mirror.

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Solution

u = -25 cm

v = 15 cm

Mirror formula $\frac{1}{f}$ = $\frac{1}{u}$ + $\frac{1}{v}$

$\frac{1}{f}$ = $\frac{1}{15}$ – $\frac{1}{25}$

f = 37.5 cm

Focal length of the mirror is 37.5 cm

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An object is placed at 25 cm from a convex mirror. Its image is formed 15 cm from the mirror. Find the focal length of the mirror.

u = -25 cm v = 15 cm Mirror formula 1f = 1u + 1v 1f = 115 – 125 f = 37.5 cm Focal length of the mirror is 37.5 cm

u = -25 cm

v = 15 cm

Mirror formula $\frac{1}{f}$ = $\frac{1}{u}$ + $\frac{1}{v}$

$\frac{1}{f}$ = $\frac{1}{15}$ – $\frac{1}{25}$

f = 37.5 cm

Focal length of the mirror is 37.5 cm