Two waves of frequencies $20 Hz$ and $30 Hz$ travel out from a common point. The phase difference between them after $0.6 s$ is:

In a wave,the path difference corresponding to a phase difference of $\phi$ is

The equation of a sound wave is $y = 0.0015 \sin (62.4x + 316t)$. The wavelength of this wave is ..... $unit$.

$A$ wave on a string is travelling and the displacement of particles on it is given by $x = A \sin (2t - 0.1x)$. Then the wavelength of the wave is

The equation of a simple harmonic wave is given by $y = 3 \sin \frac{\pi}{2}(50t - x)$,where $x$ and $y$ are in metres and $t$ is in seconds. The ratio of maximum particle velocity to the wave velocity is

If the frequency of a wave is increased by $25 \%$,then the change in its wavelength is (medium not changed).