Light of wavelength 5865 nm illuminates a slit of width 066

Light of wavelength 586.5 nm illuminates a slit of width 0.66 mm.

(a) At what distance (in meters) from the slit should a screen be placed if the first minimum in the diffraction pattern is to be 0.95 mm from the central maximum?


(b) Calculate the width (in mm) of the central maximum.

Solution

a) L = a y / m lambda

= (6.6 * 10^-4 * 9.5 * 10^-4) / (1 * 586.5 * 10^-9)

= 1.069 m

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b) w = 2 y₁

= 2 * 0.95 * 10^-3

= 0.0019 m = 1.9 mm