Two identical harmonic pulses travelling in opposite directions in a taut string approach each other. At the instant when they completely overlap,the total energy of the string will be

Out of the given four waves $(1), (2), (3)$ and $(4)$:
$y = a \sin(kx + \omega t)$ ......$(1)$
$y = a \sin(\omega t - kx)$ ......$(2)$
$y = a \cos(\omega t - kx)$ ......$(3)$
$y = a \cos(kx + \omega t)$ ......$(4)$
emitted by four different sources $S_1, S_2, S_3$ and $S_4$ respectively,interference phenomena would be observed in space under appropriate conditions when:

Obtain the resultant wave of more than two wave functions by representing the superposition principle mathematically.

The resultant amplitude due to the superposition of two waves $y_1 = 5 \sin (\omega t - kx)$ and $y_2 = -5 \cos (\omega t - kx - 150^{\circ})$ is:

If two waves having amplitudes $2A$ and $A$ and same frequency and velocity,propagate in the same direction in the same phase,the resulting amplitude will be

Two waves are propagating to point $P$ along a straight line,produced by two sources $A$ and $B$ of simple harmonic motion and equal frequency. The amplitude of every wave at $P$ is $a$. The phase of $A$ is ahead by $\frac{\pi}{3}$ compared to $B$,and the distance $AP$ is greater than $BP$ by $50 \ cm$. If the wavelength is $1 \ m$,what will be the resultant amplitude at point $P$?