The equation $\overrightarrow{\phi}(x, t) = \overrightarrow{j} \sin \left( \frac{2\pi}{\lambda} vt \right) \cos \left( \frac{2\pi}{\lambda} x \right)$ represents:

The given diagram shows a detector placed between a transmitter of sound waves and a metal plate. At three adjacent points,$R, S$ and $T$,the meter shows zero intensity. Which of the following is the frequency of the emitted wave in $Hz$? (Take the velocity of sound as $v = 300 \, m/s$)

The $(x, y)$ coordinates of the corners of a square plate are $(0, 0), (L, 0), (L, L)$ and $(0, L).$ The edges of the plate are clamped and transverse standing waves are set up in it. If $u(x, y)$ denotes the displacement of the plate at the point $(x, y)$ at some instant of time,the possible expression$(s)$ for $u$ is(are) ($a =$ positive constant).

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 $\text{ cm}$)

When a string is stretched between two rigid supports,kept under a certain tension,and vibrated,what is the nature of the standing wave formed?

Consider the three waves $z_1, z_2$ and $z_3$ as $z_1 = A \sin(kx - \omega t)$,$z_2 = A \sin(kx + \omega t)$ and $z_3 = A \sin(ky - \omega t)$. Which of the following represents a standing wave?