Question

What is the time period of visible light for which human eye is most sensitive?

(a) 1.85 × 10^15 s

(b) 1.85 × 10^-15 s

(c) 3 × 10^8s

(d) 5 × 10^16 s

This question was addressed to me in unit test.

This key question is from Electromagnetic Waves topic in section Electromagnetic Waves of Physics – Class 12

Answer 1

The correct answer is (b) 1.85 × 10^-15 s

Explanation: T = \(\frac {1}{v}\)

T = \(\frac {\lambda }{c}\)

T = 5550 × \(\frac {10^{-10}}{3}\) × 10^8

T = 1.85 × 10^-15 s.