Q: The magnitude of focal length of a concave lens is 2 m. What is the power of the lens?
(a)+0.5 dioptre
(b)-0.5 dioptre
(c)+2.0 dioptre
(d)-1.0 dioptre
Correct Answer: (b)
The correct answer is (d) '-1·0 डायॉप्टर'. This question from the General Studies domain tests knowledge of Miscellaneous.