Two sinusoidal waves of the same frequency travel in the same direction along a string. If `A_(1) =m 3.0 cm, A_(2) = 4.0 cm, phi_(1) = 0`, and `phi_(2) = pi//2 rad`, what is the amplitude of the resultant wave ?

Explanation

Resultant amplitude `= sqrt(3^(2) + 4^(2) + 2 xx 3 xx 4 xx cos 90^(@)) = 5 cm`.