Two waves represented by $y_1 = a \sin \frac{2\pi}{\lambda} (vt - x)$ and $y_2 = a \cos \frac{2\pi}{\lambda} (vt - x)$ are superposed. The resultant wave has an amplitude equal to

Two waves of the same frequency and same amplitude $a$ are superimposed. If the resultant amplitude is also $a$,what is the phase difference between the two waves?

Two waves have equations $x_1 = a \sin(\omega t + \phi_1)$ and $x_2 = a \sin(\omega t + \phi_2)$. If the frequency and amplitude of the resultant wave remain equal to those of the superimposing waves,then the phase difference between them is:

Two waves represented by $y_1 = 10 \sin(2000 \pi t + 2x)$ and $y_2 = 10 \sin(2000 \pi t + 2x + \frac{\pi}{2})$ are superposed at any point at a particular instant. The resultant amplitude is ..... $unit$.

$A$ person standing at a distance of $6\, m$ from a source of sound receives sound waves in two ways: one directly from the source and the other after reflection from a rigid boundary,as shown in the figure. The maximum wavelength for which the person will receive maximum sound intensity is .... $m$.

Two waves of amplitudes $A_1$ and $A_2$ respectively are superimposed. The ratio between the maximum and minimum intensities of the resultant waves is $9 : 4$. The value of $A_2 / A_1$ is [Assume $A_1 > A_2$]