A slit S is illuminated by a monochromatic source of light to give two coherent sources `P_1`, and `P_2`, These give a dark band at a point on the screen If the distance between `P_1`, and `P_2`, is 1 mm and the screen is placed in 1m away, what is the fringe separation for a light of wavelength `5 x 10^-7`m?

Find the distance between the points P(-2,4,1) .and Q(1,2,-5) .

A long narrow slit is illuminated by blue light and the diffraction pattern is obtained on a white screen:-In a double slit experiment, the slits are separated by 0.03 cm and the screen is placed 1.5 m away. The distance between the central fringe and the fourth bright is 1 cm. Determine the wavelength of light used in the experiment.