The interference pattern is obtained with two coherent light sources of intensity ratio $4:1$. If the ratio $\frac{I_{\max} + I_{\min}}{I_{\max} - I_{\min}}$ is $\frac{5}{x}$,then the value of $x$ will be equal to:

Two waves of intensity ratio $1:9$ cross each other at a point. The resultant intensities at the point are $I_1$ when the waves are incoherent and $I_2$ when the waves are coherent with a phase difference of $60^{\circ}$. If $\frac{I_1}{I_2} = \frac{10}{x}$,then $x = . . . . . . . . . . .$

An interference pattern is observed at $P$ due to the superimposition of two rays coming from a source $S$ as shown in the figure. The value of $l$ for which maxima is obtained at $P$ is: ($R$ is a perfectly reflecting surface)

Two coherent sources of intensities $I_1$ and $I_2$ produce an interference pattern on a screen. The maximum intensity $I_{max}$ in this interference pattern is:

Two waves having amplitudes in the ratio $5:1$ produce interference. The ratio of the maximum to minimum intensity is

Two beams of light having intensities $I$ and $4I$ interfere to produce fringes on a screen. The phase difference between the beams at point $A$ is $\pi/2$ and at point $B$ is $2\pi$. Find the resultant intensities at points $A$ and $B$.