When the tense wire of a sitar is pulled slightly from the middle and then released,which type of waves are produced?

$A$ parallel beam of light is incident on a tank filled with water up to a height of $61.5 \,mm$ as shown in the figure below. Ultrasonic waves of frequency $0.5 \,MHz$ are sent along the length of the water column using a transducer placed at the top and they form longitudinal standing waves in the water. Which of the schematic plots below best describes the intensity distribution of the light as seen on the screen? (Take the speed of sound in water to be $1500 \,m/s$)

$A$ narrow tube is bent in the form of a circle of radius $R,$ as shown in the figure. Two small holes $S$ and $D$ are made in the tube at positions right-angled to each other. $A$ source placed at $S$ generates a wave of intensity $I_0$ which is equally divided into two parts: one part travels along the longer path,while the other travels along the shorter path. Both the waves meet at point $D$ where a detector is placed. If a maxima is formed at the detector,then the possible values for the wavelength $\lambda$ of the wave produced are given by:

$A$ transverse sinusoidal wave of amplitude $a,$ wavelength $\lambda,$ and frequency $n$ is travelling on a stretched string. The maximum speed of any point on the string is $v/10,$ where $v$ is the speed of propagation of the wave. If $a = 10^{-3} \ m$ and $v = 10 \ m/s,$ then $\lambda$ and $n$ are given by:

Column $I$ shows four systems,each of the same length $L$,for producing standing waves. The lowest possible natural frequency of a system is called its fundamental frequency,whose wavelength is denoted as $\lambda_{f}$. Match each system with statements given in Column $II$ describing the nature and wavelength of the standing waves.
Column $I$:
$(A)$ Pipe closed at one end
$(B)$ Pipe open at both ends
$(C)$ Stretched wire clamped at both ends
$(D)$ Stretched wire clamped at both ends and at mid-point
Column $II$:
$(p)$ Longitudinal waves
$(q)$ Transverse waves
$(r)$ $\lambda_{f} = L$
$(s)$ $\lambda_{f} = 2L$
$(t)$ $\lambda_{f} = 4L$

Following are expressions for four plane simple harmonic waves:
$(i) \, y_1 = A \cos 2\pi \left( n_1 t + \frac{x}{\lambda_1} \right)$
$(ii) \, y_2 = A \cos 2\pi \left( n_1 t + \frac{x}{\lambda_1} + \frac{1}{2} \right)$
$(iii) \, y_3 = A \cos 2\pi \left( n_2 t + \frac{x}{\lambda_2} \right)$
$(iv) \, y_4 = A \cos 2\pi \left( n_2 t - \frac{x}{\lambda_2} \right)$
The pairs of waves which will produce destructive interference and stationary waves respectively in a medium are: