MCQ
The equation of a wave travelling in a string can be written as $y = 3\cos \pi (100\,t - x)$. Its wavelength is .... $cm$
- A$100$
- ✓$2$
- C$5$
- DNone of the above
✓
Answer
Correct option: B.
$2$
b
(b) Comparing the given equation with $y = a\cos (\omega \,t - kx)$
We get $k = \frac{{2\pi }}{\lambda } = \pi ==> \lambda = 2cm$
(b) Comparing the given equation with $y = a\cos (\omega \,t - kx)$
We get $k = \frac{{2\pi }}{\lambda } = \pi ==> \lambda = 2cm$
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