Written Assignment 6

Answer all of the following questions. Do not send in a partially completed assignment. Answer each question as completely as possible, but do not merely copy answers from your reading materials. If you cite a reference in the text, explain the meaning of the citation.

1 In your own words, explain the meaning of the following terms:

a. Transverse waves: This means that that vibration is perpendicular to the direction the wave is traveling.

b. Longitudinal waves: This means that that vibration is parallel to the direction the wave is traveling.

c. Standing waves: This means that two waves with identical frequency traveling in opposite directions interfere with each other, creating certain points (nodes) that remain fixed

d. Shock waves: Waves that are created by a sudden change or disruption in the characteristics of the medium.

2 Police use Doppler radar to detect speeding cars. Explain how the Doppler effect is used in this application.

3 A person in a cave emits a sound and receives and echo 2.5 seconds later. How far is that person away from the wall?

Solution: The speed of sound is 344 m/s (at sea level, at \({{21}^{\text{O}}}\) C). Let d be the distance from the person to the wall. This means that

\[344=\frac{2d}{t}\Leftrightarrow 344=\frac{2d}{2.5}\Leftrightarrow 2d=344\times 2.5\Leftrightarrow d=\frac{344\times 2.5}{2}=430\text{ meters}\]

4 Why do soldiers break step in marching over a bridge?

5 Jet aircraft mechanics wearing ear protectors are able to converse with each other because the ear protectors block out the sound of the jet engine. What physics concept would account for this?

6 Suppose you call your dog with an average intensity level of 80 decibels (db). How much more sound energy would you have to put into each call to:

a. Increase to 90 db?

b. Increase to 100 db?

Price: $12.95

Solution: The downloadable solution consists of 3 pages, and 571 words
Deliverable: Word Document and pdf