Question 16

In double-slit experiment using light of wavelength 600 nm, the angular width of a fringe formed on a distant screen is 0.1^{o}. What is the spacing between the two slits?

Answer

It is given that,

Wavelength of light used, λ = 6000 nm = 600 × 10 ^{-9} m

Angular width of fringe, *θ = 0.1° = 0.1 x ¶/180 = 3.14/1800 rad*

Angular width of a fringe is related to slit spacing (d) as: *d = λ/θ* = 600 x 10^{-9}/3.14/1800 = 3.44 x 10^{-4} m

Therefore, the spacing between the slits is 3.44 x 10 -4 m.

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- Q:-
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- Q:-
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- Q:-
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- Q:-
The electrostatic force on a small sphere of charge 0.4 μC due to another small sphere of charge − 0.8 μC in air is 0.2 N.

(a) What is the distance between the two spheres?

(b) What is the force on the second sphere due to the first?

- Q:-
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