A single slit of width a is illuminated by a monochromatic light of wavelength 600 nm . The value of a for which first minimum appears at θ = 30 o on the screen will be :

Step-by-step solution

For the first minima a   sin θ = λ   The given data is θ = 30 ° λ = 600   nm The value of a is a = λ sin 30 ° = 600 × 10 - 9 1 2 = 1 . 2   μm