Standing waves are produced in $10\, m$ long stretched string. If the string vibrates in $5$ segments and wave velocity is $20\,m/s$, its frequency is
- 5 Hz
- 4 Hz
- 2 Hz
- 10 Hz
The Correct Option is A
Solution and Explanation
$\therefore 5 \frac{\lambda}{2}=10$
$\Rightarrow \lambda=4\, m$
Given, the velocity of the wave $v=20\, m / s$
$\therefore$ Frequency $v=\frac{v}{\lambda}=\frac{20}{4}=5\, s ^{-1}=5\, Hz$
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Concepts Used:
Doppler Effect
The Doppler effect is a phenomenon caused by a moving wave source that causes an apparent upward shift in frequency for observers who are approaching the source and a visible downward change in frequency for observers who are retreating from the source. It's crucial to note that the impact isn't caused by a change in the source's frequency.
The Doppler effect may be seen in any wave type, including water waves, sound waves, and light waves. We are most familiar with the Doppler effect because of our encounters with sound waves