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)

Respuesta :

Answer:

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, [tex]\lambda = 461.9 nm = 461.9 * 10^{-9} m[/tex]

The distance of the screen, R = 1 m

[tex]d sin \theta = \lambda[/tex]

where [tex]\theta[/tex] is the angle at which first minima is visible

[tex]0.0001 sin \theta = 461.9 * 10^{-9} \\sin \theta =\frac{461.9 * 10^{-9}}{0.0001} \\sin \theta = 0.004619\\\theta = sin^{-1} 0.004619\\\theta = 0.2647^{0}[/tex]

The angular width of the central maximum = [tex]2 \theta[/tex]

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

[tex]\lambda = 600 nm = 600 * 10^{-9} m[/tex]

R = 40 cm = 0.4 m

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

[tex]y = \frac{3 \lambda R}{d} \\y = \frac{3 * 600 * 10^{-9}*0.4 }{0.0001} \\y = 0.0072 m[/tex]

y = 0.72 cm