PRACTICE QUIZ 15A

Answer the following questions completely and clearly.

1. How are period and frequency related?

  

2. What is the "pitch" of a sound? What word is more scientific?

  

3. Is sound classified as a transverse or longitudinal wave? Explain why.

 

 

4. What is the Doppler Effect?

 

 

5. What happens to the intensity of a sound as it increases from 10 dB to 30 dB?

 

 

6. What is the difference between the harmonics of open-pipe resonators and the harmonics of closed-pipe resonators?

 

  

Solve the following. Show all work and circle your answer.

7. A tuning fork produces a resonance with a closed tube 14 cm long. What is the frequency of the tuning fork? (Ignore end correction for the pipe.)

 

 

 

8. An open organ pipe is 2.2 m long and is 19 cm in diameter. What are the frequencies of the lowest two harmonics on this pipe?

 

 

 

 

 

9. A closed organ pipe is 2.2 m long and is 19 cm in diameter. What are the frequencies of the lowest two harmonics on this pipe?

 

 

 

 

 

10. Many orchestras tune to a note with a frequency of 440 Hz. What is the wavelength of this note?

 

 

11. A police car is chasing a bank robber's car. The fequency of the police siren is 922 Hz, but the bank robber hears a frequency of 938 Hz. If the bank robber is driving 20 m/s, what is the speed of the police car?