MCQ
A wavelength $0.60 cm$ is produced in air and it travels at a speed of $300 ms^{-1}$. It will be an
- AAudible wave
- BInfrasonic wave
- ✓Ultrasonic wave
- DNone of the above
✓
Answer
Correct option: C.
Ultrasonic wave
c
(c) $n = \frac{v}{\lambda } = \frac{{300}}{{0.6 \times {{10}^{ - 2}}}}Hz$
(c) $n = \frac{v}{\lambda } = \frac{{300}}{{0.6 \times {{10}^{ - 2}}}}Hz$
$ = \frac{3}{6} \times {10^4}Hz = 50,000Hz$
==> Wave is ultrasonic.
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