Question

You have two lenses of focal lengths +10 cm and -10 cm respectively. State the nature and power of lens.

Answer 1

Answer:

Thick lens will have shorter and consequently thin lens will have greater focal length. Because, For a thick lens, the optical path length of the light is more, than for a thin lens, thus, the bending of light will be more in case of a thicker lens. Consequently, it has a shorter focal length. Hope it help