CameraIcon
CameraIcon
SearchIcon
MyQuestionIcon
MyQuestionIcon
Question

Two lenses A and B have focal lengths of + 20 cm and, -10 cm, respectively. (a) What is the nature of lens A and lens B ? (b) What is the power of lens A and lens B ? (c) What is the power of combination if lenses A and B are held close together ?

Open in App
Solution

a)- For converging lenses, the focal length is always positive, while diverging lenses always have negative focal lengths.
so A is converging and B is diverging lens.

b) Pa = 120=0.05D

Pb = 110=0.1D

c)-P=Pa+Pb
P=0.05-0.1=-0.05D


flag
Suggest Corrections
thumbs-up
2
BNAT
mid-banner-image