$A$ wave is represented by $x = 4 \cos \left(8t - \frac{y}{2}\right)$,where $x$ and $y$ are in $m$ and $t$ is in $s$. The frequency of the wave (in $s^{-1}$) is .........

$A$ wave travels uniformly in all directions from a point source in an isotropic medium. The displacement of the medium at any point at a distance $r$ from the source may be represented by ($A$ is a constant representing strength of source)

What is the phase change of a wave when it reflects from a rigid support?

The speed of a wave in a certain medium is $960 \,m/s$. If $900$ waves pass over a certain point of the medium in half a minute, the wavelength of the wave is (in $\,m$)

$A$ travelling wave pulse is given by $y = \frac{4}{3x^2 + 48t^2 + 24xt + 2}$,where $x$ and $y$ are in $m$ and $t$ is in $s$. The velocity of the wave is ........... $m/s$.

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