16. An observer is moving away from a stationary ambulance. According to the Doppler effect, for the observer, the apparent frequency of the siren compared to the actual frequency of the siren a. increases b. stays the same c. decreases d. resonates e. increases or decreases depending on the speed of the ambulance

24.) If you pass by a building with a siren sounding, as you move away from the building, the sound of the sirens will be a. higher pitched b. lower pitched c. the same

47.) When either the listener moves closer to the source or the source of sound moves towards the listener, the compression waves are moved closer together. The results in a. the Doppler effect b. a change in pitch is detected because a sound source is increasing in volume. c. the creation of echoes

2. Superposition of waves moving in the same direction. Two traveling waves with the equations y₁ = A sin(kx-w₁t) and y₂ = A sin(k₂x - w₂t + p) are present in a medium. (a) Find the equation of the wave function resulting from the superposition of the two waves. (b) Describe the resulting superposition wave. Can it produce stationary waves? (c) If the speed of the waves in the medium is 6 m/s, and each wave has a wavelength of 2 m and 3 m, find the superposed wave function. Draw a wave function at t = 0 s if the phase difference (i) = 0°, (ii) = 90°, and (iii) 4 ) = 180°. (d) As in point (c), but both waves have the same wavelength, say 2 m.