Two progressive waves of identical amplitude 3cm and the same frequency are represented by
y1=3sinωt,y2=3sin(ωt+60∘).
(i) Calculate the amplitude of the resultant wave.
(ii) If the intensity of a wave is proportional to the square of its amplitude, determine the intensity of the resultant wave in terms of the intensity I0 of a single wave.
(iii) By what factor does the intensity change as compared to I0?