The diagram shows a snapshot of a wave at time $t = 0$. The particle at $x = x_1$ is moving upward at that instant. The direction of propagation of the wave is:

The path difference between two waves given by the equations $y_1 = a_1 \sin \left(\omega t - \frac{2 \pi x}{\lambda}\right)$ and $y_2 = a_2 \sin \left(\omega t - \frac{2 \pi x}{\lambda} + \phi\right)$ is

$A$ sound of frequency $480 \,Hz$ is emitted from a stringed instrument. The velocity of sound in air is $320 \,m/s$. After completing $180$ vibrations, the distance covered by the wave is: (in $\,m$)

$A$ 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

$A$ plane wave is described by the equation $y = 3 \cos \left( \frac{x}{4} - 10t - \frac{\pi}{2} \right)$. The maximum velocity of the particles of the medium due to this wave is

Two waves are given by $y_1 = a \sin(\omega t - kx)$ and $y_2 = a \cos(\omega t - kx)$. The phase difference between the two waves is