wave_mechanics basics_of_mechanical_waves Question 90

Question: A micro-wave and an ultrasonic sound wave have the same wavelength. Their frequencies are in the ratio (approximately)

[Kerala (Engg.) 2002]

Options:

A) 106 : 1

B) 104 : 1

C) 102 : 1

D) 10 : 1

Show Answer

Answer:

Correct Answer: A

Solution:

$ n=\frac{v}{\lambda }\propto v $

Therefore $ \frac{n _{MW}}{n _{US}}\approx \frac{3\times 10^{8}}{3\times 10^{2}}\approx 10^{6}:1 $