The equation of a wave is given by $y = 10 \sin \left( \frac{2 \pi}{45} t + \alpha \right)$. If the displacement is $5 \text{ cm}$ at $t = 0$,then the total phase at $t = 7.5 \text{ s}$ is

The distance between two consecutive points with phase difference of $45^{\circ}$ in a wave of frequency $300 \text{ Hz}$ is $4.0 \text{ m}$. The velocity of the travelling wave is (in $\text{km/s}$):

What is the phase difference between consecutive crest and trough?

One end of a long string of linear mass density $8.0 \times 10^{-3} \; kg \; m^{-1}$ is connected to an electrically driven tuning fork of frequency $256 \; Hz$. The other end passes over a pulley and is tied to a pan containing a mass of $90 \; kg$. The pulley end absorbs all the incoming energy so that reflected waves at this end have negligible amplitude. At $t=0$,the left end (fork end) of the string $x=0$ has zero transverse displacement $(y=0)$ and is moving along the positive $y$-direction. The amplitude of the wave is $5.0 \; cm$. Write down the transverse displacement $y$ as a function of $x$ and $t$ that describes the wave on the string.

$A$ wave travelling along a string is described by the equation $y = A \sin (\omega t - k x)$. The maximum particle velocity is:

When a wave propagating in one medium enters another medium,which of the following characteristics remains constant?