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Wave Motion and Waves on a String — Physics STD 11 Science — Question

Rajasthan BoardEnglish MediumSTD 11 SciencePhysicsWave Motion and Waves on a String5 Marks
Question
A particle on a stretched string supporting a travelling wave, takes 5.0ms to move from its mean position to the extreme position. The distance between two consecutive particles, which are at their mean positions, is 2.0cm. Find the frequency, the wavelength and the wave speed.
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Answer

Time period, $\text{T}=4\times5\text{ms}$

$=20\times10^{-3}$

$=2\times10^{-2}\text{s}$

$\Rightarrow\lambda=2\times2\text{cm}$

$=4\text{cm}$

Frequency, $\text{f}=\frac{1}{\text{T}}$

$=\frac{1}{(2\times10^{-2})}=50\text{s}^{-1}$

$=50\text{Hz}$

Wave speed = $\lambda\text{f}=4\times50\text{m/s}$

$=2000\text{m/s}$

$=2\text{m/s}$

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