To produce the phenomenon of interference,we require two sources that emit radiation of:

Two coherent sources of intensities $I_{1}$ and $I_{2}$ produce an interference pattern on a screen. The maximum intensity in the interference pattern is

Two coherent monochromatic point sources $S_1$ and $S_2$ of wavelength $\lambda = 600 \ nm$ are placed symmetrically on either side of the centre of the circle as shown. The sources are separated by a distance $d = 1.8 \ mm$. This arrangement produces interference fringes visible as alternate bright and dark spots on the circumference of the circle. The angular separation between two consecutive bright spots is $\Delta \theta$. Which of the following options is/are correct?
$[A]$ $A$ dark spot will be formed at the point $P_2$
$[B]$ At $P_2$ the order of the fringe will be maximum
$[C]$ The total number of fringes produced between $P_1$ and $P_2$ in the first quadrant is close to $3000$
$[D]$ The angular separation between two consecutive bright spots decreases as we move from $P_1$ to $P_2$ along the first quadrant

The ratio of maximum and minimum intensities in an interference pattern is $36: 1$. The ratio of the amplitude of the two interfering waves will be

Two coherent monochromatic light beams of intensities $I$ and $4I$ are superimposed. The difference between maximum and minimum possible intensities in the resulting beam is $x I$. The value of $x$ is . . . .

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: