Chapter 17, Problem 96P

Four sound waves are to be sent through the same tube of air, in the same direction:

s₁(x, t) = (9.00 nm) cos(2πx− 700πt)

s₂(x, t) = (9.00 nm) cos(2πx− 700πt + 0.7π)

s₃(x, t) = (9.00 nm) cos(2πx− 700πt+π)

s₄(x, t) = (9.00 nm) cos(2πx− 700πt+ 1.7π).

What is the amplitude of the resultant wave? (Hint: Use a phasor diagram to simplify the problem.)