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3 years ago

10

An instructor wishes to determine the wavelength of the light in a laser beam. To do so, he directs the beam toward a partition

with two tiny slits separated by 0.170 mm. An interference pattern appears on a screen that lies 4.95 m from the slit pair. The instructor's measurements show that two adjacent bright interference fringes lie 1.60 cm apart on the screen.
What is the laser's wavelength (in nm) ?

1 answer:

romanna [79]3 years ago

5 0

Answer:

laser wavelength = 549.5 nm

Explanation:

Given data

separation d = 0.170 mm = 0.170 × $10^{-3}$ m

interference pattern distance D = 4.95 m

two adjacent bright interference width w = 1.60 cm = 1.60 × $10^{-2}$ m

to find out

laser's wavelength

solution

we know that fringe width formula that is

width = wavelength × distance / separation

we put all these value here to find wavelength

wavelength = 1.60 × $10^{-2}$ × 0.170 × $10^{-3}$ / 4.95

wavelength = 549.5 nm

so laser wavelength = 549.5 nm

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