Question

Calculate the frequency of the wave whose wavelength is 10nm.

(a) 2 Hz

(b) 3 Hz

(c) 1 Hz

(d) 4 Hz

I had been asked this question in a national level competition.

This interesting question is from Developments Leading to the Bohr’s Model of Atom topic in section Structure of Atom of Chemistry – Class 11

Answer 1

Right choice is (b) 3 Hz

Explanation: The relation between wavelength(λ) and frequency(v) of a wave is given by λ = c/v where c is the speed of light of the light. v = c/λ Frequency of the given wave = (3 x 10^8m/s)/(10 x 10^-9m) = 3 Hz.