Question

A lens has a power of - 2.5 diopter find focal length and nature​

Answer 1

Answer:

focal length = -1\P =1\-2.5 metre =40 cm

Step-by-step explanation:

facal length positive i.e convex lens

Answer 2

Answer:

Given:

• Lens has the power of -2.5 Dioptre

To find:

• The focal length of the mirror and the nature of the image.

Solution:

Power (P) = 1/Focal length (f)

=> - 2.5 = 1/f

=> f = -1/2.5

=> f = - 0.4 m

Since, the focal length is negative so ,the lens is concave.and the image will be formed behind the mirror.