Question

A concave makeup mirror is designed so the virtual image it produces is four times the size of the object when the distance between the object and the mirror is 18.0 cm. What is the radius of curvature of the mirror?

Answer 1

Radius of curvature = 48 cm.

Step-by-step explanation:

Given that

Magnification,m=4

Distance between object and mirror,u=18 cm

We know that magnification of concave mirror given as

m= -v/u

So

4 = -v/18

v= - 72 cm

As we know that

`(1)/(f)=(1)/(u)+(1)/(v)`

`(1)/(f)=(1)/(18)-(1)/(72)`

f=24 cm

So r= 2 x f

r=48 cm

Radius of curvature = 48 cm.