Q. A micro-wave and an ultrasonic sound wave have the same wavelength. Their frequencies are in the ratio (approximately)
A) $10^{6}\ :1$
B) $10^{4}\ :1$
C) $10^{2}\ :1$
D) $10\ :1$
Explanation
(a) $n = \frac{v}{\lambda} \propto v \Rightarrow \frac{n_{MW}}{n_{US}} \approx \frac{3 \times 10^{8}}{3 \times 10^{2}} \approx 10^{6}\ :1$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.