The phase difference corresponding to a path difference of $x$ 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 $\text{ m s}^{-1}$)

Give the definition,$SI$ unit,and dimensional formula of the time period,angular frequency,and frequency of a wave.

Write the definition of the time period of a wave.

The equation of a transverse wave travelling along a string is $y(x, t) = 4.0 \sin(20 \times 10^{-3} x + 600 t) \ mm$,where $x$ is in $mm$ and $t$ is in seconds. The velocity of the wave is:

In a plane progressive harmonic wave,the particle speed is always less than the wave speed if: