Two simple harmonic waves having equal amplitudes of $8\,cm$ and equal frequency of $10\,Hz$ are moving along the same direction. The resultant amplitude is also $8\,cm$. The phase difference between the individual waves is $..................$ degree.

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:

Two pulses on a string approach each other at speeds of $1 \ m/s$. What is the shape of the string at $t = 3 \ s$ :-

Two waves originating from $S_1$ and $S_2$,having zero initial phase difference and common wavelength $\lambda$,will show completely destructive interference at $P$,if $(S_1 P - S_2 P)$ is

Two waves with same amplitude and frequency superpose at a point. The ratio of resultant intensities when they arrive in phase to that when they arrive $90^{\circ}$ out of phase is $\left[\cos \frac{\pi}{2}=0\right]$

Two loudspeakers ($L_1$ and $L_2$) are placed with a separation of $10 \ m$, as shown in the figure. Both speakers are fed with an audio input signal of the same frequency with constant volume. $A$ voice recorder, initially at point $A$, at equidistance to both loudspeakers, is moved by $25 \ m$ along the line $AB$ while monitoring the audio signal. The measured signal was found to undergo $10$ cycles of minima and maxima during the movement. The frequency of the input signal is . . . . . . $Hz$. (Speed of sound in air is $324 \ m/s$ and $\sqrt{5} = 2.23$)