(II) Suppose two linear waves of equal amplitude and frequency have a phase difference ϕ as they travel in the same medium. They can be represented by ₁ ₂ ω θ
D₁ = A sin (kx - ωt)
D₂ = A sin ( kx - ωt + ϕ)
(b) What is the amplitude of this resultant wave? Is the wave purely sinusoidal, or not?

"(II) Suppose two linear waves of equal amplitude and frequency have a phase difference ϕ as they travel in the same medium. They can be represented by ₁ ₂ ω θ

D₁ = A sin (kx - ωt)

D₂ = A sin ( kx - ωt + ϕ).

(d) Describe the resultant wave, by equation and in words, if ϕ = π/2 ."

(II) The two sources of sound in Fig. 16–15 face each other and emit sounds of equal amplitude and equal frequency (305 Hz) but 180° out of phase. For what minimum separation of the two speakers will there be some point at which

(b) complete destructive interference occurs? (Assume T = 20°C .)

(I) The two pulses shown in Fig. 15–37 are moving toward each other. (a) Sketch the shape of the string at the moment they directly overlap.

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(I) The two pulses shown in Fig. 15–37 are moving toward each other. (c) In Fig. 15–37, at the moment the pulses pass each other, the string is straight. What has happened to the energy at this moment?

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In the following figure, two interfering waves are drawn at some instance in time. 

a. Indicate the regions on the graph where constructive interference occurs.
b.Indicate the regions on the graph where destructive interference occurs.