Question
Define lens and write its formula.
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Answer
Any transparent medium surrounded by two surfaces, one of which or both surfaces are spherical is called lens. There are two types of lenses-(1) Convex lens (2) Concave lens.
The relationship between the distances of the object, the distance of the image and the focal length of the lens is called lens formula. i.e., $-\frac{1}{u}+\frac{1}{v}=\frac{1}{f}$.
The relationship between the distances of the object, the distance of the image and the focal length of the lens is called lens formula. i.e., $-\frac{1}{u}+\frac{1}{v}=\frac{1}{f}$.
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