Question
Question: A thin plano convex lens acts like a concave mirror of focal length 0.2 m when silvered on its plane...
A thin plano convex lens acts like a concave mirror of focal length 0.2 m when silvered on its plane surface. The refractive index of lens is 1.5. The radius of curvature of convex surface of the lens is :
A
0.1 m
B
0.2 m
C
0.4 m
D
0.8 m
Answer
0.2 m
Explanation
Solution
f = 
– 0.2 = 
R = 0.2 m.