The equation of a stationary wave is $y = 20 \sin(\pi x) \cos(\omega t)$,where $x$ and $y$ are in meters and $t$ is in seconds. The distance between a node and its adjacent antinode is (in $\text{ cm}$)

The speed of a stationary wave represented by the equation $y = 0.7 \sin \left(\frac{7 \pi}{4} x\right) \cos (350 \pi t)$ is (In the given equation $x$ and $y$ are in metre and $t$ is in second). (in $m \ s^{-1}$)

$A$ stationary wave is formed with $3$ nodes along the length of a string of $90 \ cm$. The wavelength of the wave is: (in $cm$)

Two travelling waves ${y_1} = A\sin [k(x - ct)]$ and ${y_2} = A\sin [k(x + ct)]$ are superimposed on a string. The distance between adjacent nodes is

The ends of a stretched wire of length $L$ are fixed at $x = 0$ and $x = L.$ In one experiment,the displacement of the wire is ${y_1} = A\sin (\pi x/L)\sin \omega t$ and energy is ${E_1}$,and in another experiment its displacement is ${y_2} = A\sin (2\pi x/L)\sin 2\omega t$ and energy is ${E_2}$. Then

Standing stationary waves can be obtained in an air column even if the interfering waves are