Question:
The given graph (Fig. 2) shows the displacement versus time relation for a disturbance travelling with velocity of 1500 the wavelength of the disturbance.
Solution:
Here $v=1500 \mathrm{~m} \mathrm{~s}^{-1}$
$T=2 \mu s=2 \times 10^{-6} \mathrm{~s}$
$\therefore$ Frequency,
$v=\frac{1}{T}=\frac{1}{2 \times 10^{-6}}=5 \times 10^{5} \mathrm{~Hz}$
Using $v=v \hat{\lambda}$, we get
$\lambda=\frac{v}{v}=\frac{1500}{5 \times 10^{5}}=3 \times 10^{-3} \mathrm{~m}=3 \mathrm{~mm}$