In a Young's double slit setup, the slits are illuminated by a white light source. Which colour of light will form the first-order bright fringe closest to the central white maximum on the viewing screen?

Step-by-step solution

The position of the n -th order bright fringe from the central maximum in Young's double slit experiment is given by y_n = n D d . For the first-order bright fringe, n = 1 , which gives y₁ = D d . The distance y₁ is directly proportional to the wavelength of the light. Among the colours of visible light, violet has the shortest wavelength ( _ violet Since violet light has the minimum wavelength, its first-order bright fringe will be formed at the minimum distance from the central maximum. Therefore, violet will be