Answer:
Radius of curvature = 48 cm.
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
[tex]\dfrac{1}{f}=\dfrac{1}{u}+\dfrac{1}{v}[/tex]
[tex]\dfrac{1}{f}=\dfrac{1}{18}-\dfrac{1}{72}[/tex]
f=24 cm
So r= 2 x f
r=48 cm
Radius of curvature = 48 cm.