$A$ string of mass $m$ and length $l$ hangs from a ceiling as shown in the figure. $A$ wave in the string moves upward. $v_A$ and $v_B$ are the speeds of the wave at points $A$ and $B$ respectively. Then $v_B$ is

$A$ string $1\,m$ long is driven by a $300\,Hz$ vibrator attached to its end. The string vibrates in three segments. The speed of transverse waves in the string is equal to ..... $m/s$.

$A$ uniform thin rope of length $12 \, m$ and mass $6 \, kg$ hangs vertically from a rigid support and a block of mass $2 \, kg$ is attached to its free end. $A$ transverse short wavetrain of wavelength $6 \, cm$ is produced at the lower end of the rope. What is the wavelength of the wavetrain (in $cm$) when it reaches the top of the rope?

$A$ uniform rope of length $L$ and mass $m_1$ hangs vertically from a rigid support. $A$ block of mass $m_2$ is attached to the free end of the rope. $A$ transverse wave of wavelength $\lambda_1$ is produced at the lower end of the rope. The wavelength of the wave when it reaches the top of the rope is $\lambda_2$. The ratio $\frac{\lambda_1}{\lambda_2}$ is

$A$ wire of length $50 \ cm$ and weighing $10 \ g$ is attached to a spring at one end and to a fixed wall at the other end. The spring has a spring constant of $50 \ N/m$ and is stretched by $1 \ cm$. If a wave pulse is produced on the string near the wall, then how much time will it take to reach the spring (in $s$)?

The given graph illustrates a transverse wave travelling on a string at a particular instant,and the points $P, Q, R$ and $S$ represent elements of the string. Which of the following statements about the motion of the elements is correct?