The equation of a wave is given by $Y = 7 \sin(7\pi t - 0.04\pi x + \frac{\pi}{3})$. What is the wave speed in $m/s$?

If a travelling wave is given by $y(x, t) = 0.5 \sin (70.1 x - 10 \pi t)$,where $x$ and $y$ are in metre,the time $t$ is in second,then the frequency of the wave is (in $Hz$)

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 $\,Hz$)

$A$ transverse wave propagating along the $x-$ axis is represented by $y(x,t) = 8.0 \sin \left( 0.5\pi x - 4\pi t - \frac{\pi}{4} \right)$,where $x$ is in metres and $t$ is in seconds. The speed of the wave is ..... $m/s$.

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 ..... $m/s$.

$A$ travelling wave passes a point of observation. At this point,the time interval between successive crests is $0.2 \ s$. Which of the following is true?