The equation of a progressive wave is $y = a \sin(200t - x)$,where $x$ is in meters and $t$ is in seconds. The velocity of the wave is ..... $m/s$.

The phase difference corresponding to a path difference of $x$ is

Waves having a velocity $10 \text{ m/s}$ strike a stationary boat near the sea shore. The distance between two consecutive crests of the waves is $40 \text{ m}$. After how many seconds do the consecutive waves strike the boat (in $\text{ s}$)?

When a wave enters into a rarer medium from a denser medium,the property of the wave which remains constant is

$A$ body sends a wave $150 \text{ mm}$ long through medium $P$ and $0.30 \text{ m}$ long in medium $Q$. If velocity of the wave in medium $P$ is $80 \text{ cm s}^{-1}$, the velocity of wave in medium $Q$ is (in $\text{ m s}^{-1}$)

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