Consider the interference of two sources with intensities $I$ and $4I$. Find the intensity at a point where the phase difference is $\pi/2$. (in $I$)

Two light waves with amplitudes in the ratio $3 : 1$ produce interference. The ratio of the maximum to minimum intensity is

The intensity of light depends upon:

Two light waves of intensities $I$ and $4I$ superpose at a point with a phase difference of $\pi / 2$. Calculate the resultant amplitude at that point.

Four light sources produce the following four waves:
$(i)$ $y_1 = a \sin(\omega t + \phi_1)$
(ii) $y_2 = a \sin(2\omega t)$
(iii) $y_3 = d' \sin(\omega t + \phi_2)$
(iv) $y_4 = d' \sin(3\omega t + \phi)$
Superposition of which two waves gives rise to interference?

The resultant amplitude of coherent sources depends on ......