MCQ
The speed of a wave in a medium is $760\, m/s$. If $3600 $ waves are passing through a point, in the medium in $2$ minutes, then its wavelength is ...... $m$
- A$13.8$
- ✓$25.3$
- C$41.5$
- D$57.2 $
✓
Answer
Correct option: B.
$25.3$
b
(b) Frequency of wave is $n = \frac{{3600}}{{2 \times 60}}\,Hz$
(b) Frequency of wave is $n = \frac{{3600}}{{2 \times 60}}\,Hz$
==>$\lambda = \frac{v}{n} = \frac{{760}}{{30}} = 25.3\,m.$
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