Two coherent waves produce intensities 9I and 4I separately at a point. If the relative phase can vary through all possible values, find I(max) ÷ I(min).

Question

G1 Physics · Accepted Answer

The corresponding amplitudes are 3√I and 2√I. Therefore, I(max) = (3√I+2√I)² = 25I, and I(min) = (3√I−2√I)² = I. Hence, I(max) ÷ I(min) = 25. Therefore the answer is 25.