the image formed on a screen by a concave mirror of radius 20 cm is 3 times the size of the object. what is the distance of the screen from the mirror?

Given that,

Radius of mirror = 20 cm

Size of image = 3 times of size of object

We need to calculate the distance of the screen from the mirror

Using formula of magnification

Where, h' = size of image

h = size of object  

v = image distance from mirror

u = object distance from mirror

Put the value into the formula

The distance of image will three times of object distance.

Hence, The distance of the screen from the mirror is 3u.

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