Two simple harmonic waves having equal amplitudes of 8 cm and equal frequency of 10 Hz are moving along the same direction. The resultant amplitude is also 8 cm . The phase difference between the individual waves is _____ degree.

Step-by-step solution

If two waves have the same amplitude, frequency, and direction, but are out of phase by ϕ degrees, then the amplitude of the resultant waves is given by A R = 2 A cos Δ ϕ 2 Here, A 1 = A 2 = A R = 8   cm So, cos Δ ϕ 2 = 1 2 Or phase difference between the individual waves is Δ ϕ 2 = 60 ° ⇒ Δ ϕ = 120 ° .