The displacement of a travelling wave $y=C \sin \frac{2 \pi}{\lambda}$ (at $-x$ ) where $t$ is time, $x$ is…
The displacement of a travelling wave $y=C \sin \frac{2 \pi}{\lambda}$ (at $-x$ ) where $t$ is time, $x$ is distance and $\lambda$ is the wavelength, all in S.I. units. Then the frequency of the wave is
$\frac{2 \pi \lambda}{a}$
$\frac{2 \pi a}{\lambda}$
$\frac{\lambda}{a}$
$\frac{a}{\lambda}$
Solution
$y=c \sin \frac{2 \pi}{\lambda}($ at $-x)$
$y=c \sin \left(\frac{2 \pi}{\lambda}\right.$ at $\left.-\frac{2 \pi}{\lambda} x\right)$
Comparing with $y=A \sin (\omega \hbar-k x)$
$\omega=2 \pi f=\frac{2 \pi a}{\lambda}$
$f=\frac{a}{\lambda}$