In Fraunhofer diffraction, how is the angular width of the central bri

1.	In Fraunhofer diffraction, how is the angular width of the central bright fringe affected when slit separation is increased ?
Answer» Angular width of central maxima = 2θ = ±\(\frac{2\lambda}{a}\) If D be the distance between the slit and the screen, then linear width 'x' of the central maxima is given by x = d x 2θ = D x \(\frac{2\lambda}{a}\) = \(\frac{2D\lambda}{a}\) As the width of the slit(a) is increased, the linear and angular width of central maxima goes on decreasing because x ∝ \(\frac{1}{a}\)

In Fraunhofer diffraction, how is the angular width of the central bright fringe affected when slit separation is increased ?

Answer»

Angular width of central maxima = 2θ = ±\(\frac{2\lambda}{a}\)

If D be the distance between the slit and the screen, then linear width 'x' of the central maxima is given by

x = d x 2θ = D x \(\frac{2\lambda}{a}\) = \(\frac{2D\lambda}{a}\)

As the width of the slit(a) is increased, the linear and angular width of central maxima goes on decreasing because x ∝ \(\frac{1}{a}\)