Question

A microwave and an ultrasonic sound wave have the same wavelength. Their frequencies are in the ratio (approximately)

• A. $10^2$
• B. $10^4$
• C. $10^6$
• D. $10^8$

Answer 1

Answer: (C)

Frequency of microwaves, ${\upsilon }_m\approx 10^{11}Hz$
Frequency of ultrasonic sound waves, ${\upsilon }_u\approx 10^{5}Hz$
$\therefore \frac{{\upsilon }_m}{{\upsilon }_u}=\frac{10^{11}}{10^5}=10^6$