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3 years ago

A shaving or makeup mirror is designed to magnify your face by a factor of 1.40 when your face is placed 20.0cm in front of it

Physics

1 answer:

Dennis_Churaev [7]3 years ago

5 0

Answer:

(a) convex mirror

(b) virtual and magnified

Explanation:

The having mirror is convex mirror.

distance of object, u = - 20 cm

magnification, m = 1.4

(a) As the image is magnified and virtual , so the mirror is convex in nature.

(b) The image is virtual and magnified.

Use the formula of magnification.

$m =-\frac{v}{u}\\1.4=-\frac{v}{-20}\\v =28 cm$

Use the mirror equation, let the focal length is f.

$\frac{1}{f}=\frac{1}{v}+\frac{1}{u}\\\frac{1}{f}=\frac{1}{28}+\frac{1}{20}\\\frac{1}{f}=\frac{28+20}{560}\\f=11.67cm$

Radius of curvature, R = 2 f = 2 x 11.67 = 23.3 cm

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3 years ago

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3 years ago

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lyudmila [28]

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