Question

1. A student uses a lens of focal
length 40 cm and another of -20 cm. Write the nature and power of each lens.​

Answer 1

Answer:

concave lens is the nature of lebs

Answer 2

Answer:

P=1/f

= 1/40

=0.025

therefore power of first lens is 0.025

since the power is positive

therefore it is a convex lens

P= 1/f

= 1/-20

= -1/20

= -0.05

since the power is negative

therefore it is a concave lens.

Explanation:

hope this helps!