Chapter 2: Q2DQ (page 537)
The hero of a western movie listens for an oncoming train by putting his ear to the track. Why does this method give an earlier warning of the approach of a train than just listening in the usual way?
The speed of the sound is more in metal so the warning is obtained earlier than the air medium.
Over 30 million students worldwide already upgrade their learning with Vaia!
All the tools & learning materials you need for study success - in one app.
Get started for free
If you are riding in a supersonic aircraft, what do you hear? Explain. In particular, do you hear a continuous sonic boom? Why or why not?
Longitudinal Waves on a Spring. A long spring such as a
(see Section 16.2). (b) Evaluate v for a spring with m = 0.250 kg, L = 2.00 m, and k′ = 1.50 N/m.
The motors that drive airplane propellers are, in some cases, tuned by using beats. The whirring motor produces a sound wave having the same frequency as the propeller. (a) If one single-bladed propeller is turning at 575rpm and you hear 2Hz beats when you run the second propeller, what are the two possible frequencies (in rpm) of the second propeller? (b) Suppose you increase the speed of the second propeller slightly and find that the beat frequency changes to 2.1Hz. In part (a), which of the two answers was the correct one for the frequency of the second single-bladed propeller? How do you know?
For cranial ultrasound, why is it advantageous to use frequencies in the
A baby’s mouth is 30 cm from her father’s ear and 1.50 m from her mother’s ear. What is the difference between the sound intensity levels heard by the father and by the mother?
What do you think about this solution?
We value your feedback to improve our textbook solutions.
