Q

A dentist uses a mirror to obtain a large image of a patient’s tooth. Which mirror should the dentist use and why?

RRB JE 25/02/2026 / 4:30 PM - 6:00 PM 2026
✓ Answer: B Concave mirror, because it gives a magnified image
For a convex lens, the principal focus lies on the side opposite the incident light. Under the Cartesian sign convention this focal length is positive.