Q. The wavelength of ultrasonic waves in air is of the order of
A) $5 \times 10^{- 1}cm$
B) $5 \times 10^{- 3}cm$
C) $5 \times 10^{1}cm$
D) $5 \times 10^{3}cm$
Explanation
(a) $\lambda = \frac{v}{n};n \approx 50,000\ Hz,\ v = 330m/sec \Rightarrow \lambda = \frac{330}{50000}m$
$= 6.6 \times 10^{- 1}cm \approx 5 \times 10^{- 1}cm$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.