What is the wavelength of the light?

Two slits are measured to be 0.027 mm apart. When monochromatic light falls on the slits, the 4th order bright fringe falls at a 9.7 degree angle. What is the wavelength of the light?
0.980
1.13
1.14
0.860

?2017-07-05T22:59:26Z

Favorite Answer

d sinθ = mλ (for bright maxima)
=>
λ = (d sinθ)/m
λ = [(2.7×10⁻⁵m)sin9.7°]/4
λ = 1.14×10⁻⁶ m (114 nm)