Question

the focal length of a lens is 20 cm then find its near point and the power of the lens

Answer 1

Answer:

`20(sqrt(3)-1)` and `1/(sqrt(3))` `10(sqrt(3)-1)` `20/(sqrt(3))` none of these

Answer 2

The distance from the center of the lens to the focal point is again called the focal length f of the lens. Note that the focal length and power of a diverging lens are defined as negative. For example, if the distance to F in is 5.00 cm, then the focal length is f=–5.00 cm and the power of the lens is P=–20 D.