Question

magnification of an object placed 10cm from a convex mirror of radius of curvature 20 cm will be :-

a)0.2
b)0.5
c)1
d)infinity

Answer 1

Hi Sister,

Here is your answer,

It is 0.5

Answer 2

The correct answer of this question is option b ) 0.5

Given

An object placed 10 cm in front of a convex mirror. So u = 10

The radius of curvature is ( r ) = 20 cm.

To Find

The magnification of the object ( m )

Solution

Since the object is placed in front of the convex mirror so u = - 10

and the focal length = Radius of Curvature / 2 = r/2

so f = r/2 = 20 / 2 = 10 cm

So first we need to find v

Applying mirror formula

1/u + 1/v = 1/f

On putting values

1/( -10) + 1/v = 1/10

1/v = 2/10

1/v = 1/5

v = 5 cm

Magnification m = - v/u

m = - 5/-10

m = 0.5

So the correct answer of this question is option b ) 0.5

#SPJ6