Question

How To identify the type of spherical lenses or mirror if focal length is given​

Answer 1

For spherical lense,

If the focal length is given, calculate its power which is Dioptre(D). It is given by the formula

$D=1/focal \: length \: in \: m$

If the power is positive, the lens is convex.

If the power is negative, the lens is concave.

Hope it helps.

Answer 2

udhenelol..........

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