Three coherent point sources `S_(1),S_(2) and S_(3)` are placed on a line perpendicular to the screen as shown in the figure. The wavelength of the light emitted by the sources is lambda. The distance between adjacent sources is `d=3lambda` The distance of `S_(2)` from the screen is D`(gtgt lambda)`. Find the minimum (non zero) distance x of a point P on the screen at which complete darkness is obtained.

Two coherent sources S_(1)" and "S_(2) are separated by a small distance d. The fringes obtained on the screen will be:

Two coherent point sources S_1 and S_2 are separated by a small distance d as shown. The fringes obtained on the screen will be

Two coherent point sources S_1 and S_2 are separated by a small distance d as shown. The fringes obtained on the screen will be

Two coherent point sources S_1 and S_2 are separated by a small distance d as shown. The fringes obtained on the screen will be

Two coherent point sources S_1 and S_2 are separated by a small distance d as shown. The fringes obtained on the screen will be

Two coherent monochromatic point sources S_1 and S_2 are placed in front of an infinite screen as shown in figure. Wavelength of the light emitted by both the sources is zero. Initial phase difference between the sources is zero. Initially S_(1)S_(2)=2.5 lambda and the number of bright circular rings on the screen in n_(1) . if the distance S_(1)S_(2) is increased and made 5.7 lambda , the number of bright circular rings becomes n_(2) . the difference n_(2)-n_(1) is

Two coherent monochromatic point sources S_1 and S_2 are placed in front of an infinite screen as shown in figure. Wavelength of the light emitted by both the sources is zero. Initial phase difference between the sources is zero. Initially S_(1)S_(2)=2.5 lambda and the number of bright circular rings on the screen in n_(1) . if the distance S_(1)S_(2) is increased and made 5.7 lambda , the number of bright circular rings becomes n_(2) . the difference n_(2)-n_(1) is

In the arrangement shown in the following figure, the wavelength of light used is lambda . The distance between slits S_(1) and S_(2) is d (« D). The distance between S_(3) and S_(4) is u=lambda D // 3d . If the ratio of maximum to minimum intensity observed on screen is k. Find k.