if a covex lens is cut horizontally from the middle what will happen to its focal length?also consider the case of a concave lens.

_{1}and R

_{2}will remain same as before.

As focal length is given by formula :-

$\frac{1}{f}=\left(\mu -1\right)\left(\frac{1}{{R}_{1}}-\frac{1}{{R}_{2}}\right)$ ( By Lens Maker formula )

As R

_{1}and R

_{2}do not change, so there will be no change in focal length of the lens.

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