Question

A concave mirror, of aperture $4cm$, has a point object placed on its principal axis at a distance of $10cm$ from the mirror. The image, formed by the mirror, is not likely to be a sharp image. State the likely reason for the same.

Answer 1

This is because of spherical aberration. The mirror has a very large aperture when compared to the size of the object and hence all marginal rays will not converge on the focus, resulting in a blurred image(not sharp image).