Exam 17: Waves in Two and Three Dimensions

What characteristic of sound determines the "pitch" of a musical note?

When a rocket is traveling toward a mountain at 100 m/s,the sound waves from this rocket's engine approach the mountain at speed V.If the rocket doubles its speed to 200 m/s,the sound waves from the engine will now approach the mountain at speed

Two people are talking at a distance of 3.0 m from where you are and you measure the sound intensity as 1.1 × 10^-7 W/m².Another student is 4.0 m away from the talkers.What sound intensity does the other student measure? Assume that the sound spreads out uniformly and undergoes no significant reflections or absorption.

The howler monkey is the loudest land animal and,under some circumstances,can be heard up to a distance of 8.9 km.Assume the acoustic output of a howler to be uniform in all directions and that the threshold of hearing is 1.0 × 10^-12 W/m².A juvenile howler monkey has an acoustic output of 63 µW.What is the ratio of the acoustic intensity produced by the juvenile howler to the reference intensity I₀,at a distance of 210 m?