Interference cannot be observed in two sodium lamps of equal power because the two waves do not have a .....

Light exhibits wave nature because...

Two coherent sources of intensities $I$ and $4I$ interfere. The maximum and minimum intensities of the resultant wave are:

Two light beams of intensities $I$ and $4I$ produce an interference pattern on a screen. If the phase difference between them at point $A$ is $\pi/2$ and at point $B$ is $2\pi$,find the difference between the resultant intensities at points $A$ and $B$.

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 coherent sources of intensity ratio $1 : 4$ produce an interference pattern. The fringe visibility will be