MCQ
A micro-wave and an ultrasonic sound wave have the same wavelength. Their frequencies are in the ratio (approximately)
- ✓$10^6:1$
- B$10^4:1$
- C$10^2:1$
- D$10:1$
✓
Answer
Correct option: A.
$10^6:1$
a
(a)$n = \frac{v}{\lambda } \propto v$==> $\frac{{{n_{MW}}}}{{{n_{US}}}} \approx \frac{{3 \times {{10}^8}}}{{3 \times {{10}^2}}} \approx {10^6}:1$
(a)$n = \frac{v}{\lambda } \propto v$==> $\frac{{{n_{MW}}}}{{{n_{US}}}} \approx \frac{{3 \times {{10}^8}}}{{3 \times {{10}^2}}} \approx {10^6}:1$
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