Is the focal length of convex mirror and concave lens infinity

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Solution

Dear student

The focal length of both the concave mirror and convex mirrors are not infinity rather a proper defined value. The focal length is the quantitative way of measurement of the converging or diverging power of the mirrors or the lenses. Their values can be taken as negative or positive as on the basis of the sign conventions which may vary for the mirrors and for the lenses. But the focal length will be a definite number and no infinite value.

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