Question

what is focus of the concave lens

Answer 1

heya!!! friend!!

the focus of the concave lens is the point on the principal axis where rays parallel to it meet after refraction through concave lens.

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hope it helps ya :-)

Answer 2

Concave lens are also called diverging lens. Therefore the focus of a concave lens is the point where rays parallel to the axis seem to diverge from after passing through the lens. The distance from the optical centre to this point is called the focal length ..

Hope it helped..