The focal length of a lens is (i) positive, (ii) negative. - Noon Academy

The focal length of a lens is (i) positive, (ii) negative.

Class 10 | ICSE | Physics | Refraction through a Lens | Selina

The focal length of a lens is (i) positive, (ii) negative.

In each case, state the kind of lens.

Solution:

(i) If a lens’ focal length is positive, the lens is said to be convex.
(ii) A lens is called a concave lens if its focal length is negative.

i

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