i have to do a physics assignment and i got stuck at this quesion hope u guys can help. An interference pattern is formed on a screen by the superposition of two coherent light beams, one of which has four times the intensity of the other. What is ratio of maximum to minimum intensity in the pattern? Something i find very hard to understand is how intensity is related to inteference. I know that when the waves interfere constructively intensity is max and vice versa, but other than that i dont understand how else intensity is related to interference... for example... like how is the intensity of the maximas affected when slit separation is increased.