$A$ stationary wave is represented by $y = 12 \cos \left(\frac{\pi}{6} x\right) \sin (8 \pi t)$,where $x$ and $y$ are in $cm$ and $t$ is in seconds. The distance between two successive antinodes is (in $cm$)

On producing the waves of frequency $1000 \,Hz$ in a Kundt's tube, the total distance between $6$ successive nodes is $85 \,cm$. Then, the speed of sound in the gas filled in the tube is (in $\,ms^{-1}$)

$A$ standing wave pattern is formed on a string. One of the waves is given by the equation $y_1 = a \cos(\omega t - kx + \pi/3)$. Find the equation of the other wave such that at $x = 0$,a node is formed.

What are stationary waves? Obtain their equation.

$A$ progressive wave travelling in the positive $x$-direction given by $y=a \cos (k x-\omega t)$ meets a denser surface at $x=0, t=0$. The reflected wave is then given by

The pattern of standing waves formed on a stretched string at two instants of time (extreme,mean) are shown in the figure. The velocity of the two waves superimposing to form stationary waves is $360 \, ms^{-1}$ and their frequencies are $256 \, Hz$. Which is not a possible value of $t$ (in $\sec$)?