﻿ A concave mirror forms a real image four times the size of the object placed at a distance of 10 cm from it. What is the radius of curvature of the mirror?    : Kaysons Education

# A Concave Mirror Forms A Real Image Four Times The Size Of The Object Placed At A Distance Of 10 Cm From It. What Is The Radius Of Curvature Of The Mirror?

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## Question

### Solution

Correct option is

16 cm

Since the image is erect, the magnification is negative. Hence

m = – 4.

Also               u = – 10 cm

Substituting for u and v in the formula

We have         f = –8 cm.

Hence            R = 2f = –16 cm.

The negative sign is expected since the mirror is concave.

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