What is meant by power of a lens? Write the SI unit. A student uses a lens of focal length 40 cm and another of -20cm. Write the nature and power of each lens.
Answers
Answered by
3
Answer:
Power is reciprocal of focal length. It's SI unit is Dioptre. Nature of lens of focal length 40 cm is a convex lens and its power is 100/40=2.5D . Nature of lens of focal length -20 cm is concave lens and its power is 100/-20= -5D
Explanation:
Similar questions