A single slit, 0.10 mm wide is illuminated by a wavelength of light 461.9 nm. An observing screen is 1.0 m away. What is the angular width of the central maximum? {0.53o} A single slit of width 0.1 mm is illuminated by a 600 nm light. How far is the third dark band from the central bright band on a screen 40 cm from the slit? (1.03o, 0.72 cm)

a) Angular width of the central maximum =  0.5294°

b) The distance of the third dark band from the central bright band = 0.72 cm

Explanation:

a) Width of the slit,  d = 0.1 mm = 0.0001 m

Wavelength of the light,

The distance of the screen, R = 1 m

where is the angle at which first minima is visible

The angular width of the central maximum =

Angular width of the central maximum = 2 * 0.2647

Angular width of the central maximum = 0.5294°

b)  d = 0.1 mm = 0.0001 m

R = 40 cm = 0.4 m

The distance from central bright band to third dark band, is given by the formula:

y = 0.72 cm