Question

The upper part of the bi-focal lens is a convex lens while its lower part is a concave lens.

(a) True

(b) False

The question was posed to me in examination.

The origin of the question is Optical Instruments topic in section Ray Optics and Optical Instruments of Physics – Class 12

Answer 1

Right answer is (b) False

Easy explanation: No, this is a false statement. The upper part of the bi-focal lens should be a concave lens, whereas the one used for distant vision as its lower part should be a convex lens. Such a bi-focal lens is used for reading purposes.