The equation of a plane progressive wave is given by $y = 0.025 \sin (100t + 0.25x)$. The frequency of this wave would be

Define wavelength and state its $SI$ unit.

$A$ wave is propagating along the $x$-axis. The displacement of particles of the medium in the $z$-direction at $t = 0$ is given by: $z = \exp[-(x + 2)^2]$,where $x$ is in meters. At $t = 1 \ s$,the same wave disturbance is given by: $z = \exp[-(2 - x)^2]$. Then,the wave propagation velocity is:

Velocity of sound waves in air is $330 \,m/s$. For a particular sound wave in air, a path difference of $40 \,cm$ is equivalent to a phase difference of $1.6 \pi$. The frequency of this wave is: (in $\,Hz$)

The speed of a wave in a certain medium is $960\, m/s$. If $3600$ waves pass over a certain point of the medium in $1\, minute$,the wavelength is .... $metres$.

The two waves represented by $y_1 = a \sin(\omega t)$ and $y_2 = b \cos(\omega t)$ have a phase difference of