Two monochromatic sources of electromagnetic wave $P$ and $Q$ emit waves of wavelength $\lambda =20 \mathrm{m}$ and separated by$5 \mathrm{m}$as shown. $A, B \mathrm{and} C$ are three points where interference of these waves is observed. If phase of a wave generated by $P$ is ahead of wave generated by $Q$ by $\mathrm{\pi }/2$then (given intensity of both waves is $I$) :

 

$C$ is symmetrical with respect to $P$ and $Q$

The string shown in figure is driven at a frequency of $5.00 \mathrm{Hz}$. The amplitude of the motion is $12.0 \mathrm{cm}$ and the wave speed is $20.0 \mathrm{m} {\mathrm{s}}^{-1}$. Furthermore, the wave is such that $y=0$ at $x=0$ and $t=0$. Determine (a) the angular frequency and (b) wave number for this wave. (c) Write an expression for the wave function. Calculate (d) the maximum transverse speed and (e) the maximum transverse acceleration of a point on the string.

The sketch in the figure shows displacement time curve of a sinusoidal wave at $x=8 \mathrm{m}$. Taking velocity of wave $v=6 \mathrm{m} {\mathrm{s}}^{-1}$ along positive $x$-axis, write the equation of the wave.

A transverse wave is travelling along a string from left to right. The fig. represents the shape of the string (snap-shot) at a given instant. At this instant

 (a) which points have an upward velocity

(b) which points have downward velocity

(c) which points have zero velocity

(d) which points have maximum magnitude of velocity.

In the arrangement shown in figure, the string has mass of $5\mathrm{g}$. How much time will it take for a transverse disturbance produced at the floor to reach the pulley $\mathrm{A}$ ? Take $\mathrm{g} = 10 \mathrm{m}/{\mathrm{s}}^2$.