If the amplitude ratio of two sources producing interference is $3:5$,the ratio of intensities at maxima and minima is

In the figure below,$P$ and $Q$ are two equally intense coherent sources emitting radiation of wavelength $20\, m$. The separation between $P$ and $Q$ is $5\, m$ and the phase of $P$ is ahead of that of $Q$ by $90^{\circ}$. $A, B$ and $C$ are three distinct points of observation,each equidistant from the midpoint of $PQ$. The intensities of radiation at $A, B, C$ will be in the ratio

Two light sources have amplitudes $a$ and $2a$ respectively. If they interfere with a phase difference of $\pi$,what is the resultant minimum intensity?

Two coherent sources of intensity ratio $x^2$ interfere. In the interference pattern,which of the following relations is correct?

For the sustained interference of light,the necessary condition is that the two sources should

In the phenomenon of interference :-
$(a)$ Total energy is conserved
$(b)$ Total energy is not conserved
$(c)$ Only bright fringes are formed
$(d)$ The frequency of two sources is equal