Consider the following statements A and B and identify the correct answer
A) Intensity of all bright diffraction frings is not same
B) The minima of a diffraction pattern are not perfectly dark

 The intensity is directly proportional to the square of the slit width because the intensity is directly proportional to the square of the amplitude which in turn is directly proportional to the slit width. This is because; increasing the fringe width increases the amount of light which passes onto the screen.