1 / 18

Perceiving Sound

Perceiving Sound. Before we start!. A review of Light. Light vs. Sound. What do you think is going to happen? . Make a prediction. What will happen when air is removed from the bell jar? Don’t forget to explain why. . Make Observations. Why did this happen? . Sound is… .

talli
Download Presentation

Perceiving Sound

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Perceiving Sound

  2. Before we start! • A review of Light

  3. Light vs. Sound

  4. What do you think is going to happen? • Make a prediction. • What will happen when air is removed from the bell jar? • Don’t forget to explain why.

  5. Make Observations

  6. Why did this happen?

  7. Sound is… • A mechanical wave. • Longitudinal wave. • Produced by the vibration of an object and transmitted to the object’s environment. • Requires a medium.

  8. The speed of Sound • It changes from one medium to another.

  9. Why is that? • Using the particle model to justify your answer. Why does sound travel faster in solids than in gases?

  10. The Decibel (Db) • The unit of measurement for the intensity of sound. • High Intensity sound = High amplitude = More Decibels. • Low Intensity sound = Low amplitude = Low Decibels.

  11. The Decibel Scale • All decibel measurements are not completely accurate, they are related to our perception by the human ear. • A sound measuring 0 Db is can barely be heard by the ear. • We measure variations on the scale by a factor of 10.

  12. A Sample of a Decibel Scale Another one can be found on p. 103 of your textbook.

  13. Try some Questions • P. 118 # 8- 10

  14. Pitch and Frequency • Lower Pitch = lower frequency sound. • High Pitch = Higher frequency sound.

  15. Infrasound and Ultrasounds • Infrasounds = sounds under 20Hz • Used by some animals to communicate. • E.g. Elephants • Ultrasounds = sounds above 20 000 Hz • Used in medical imaging • Used by some animals like bats (echolocation)

  16. Can we hear all frequencies?

  17. What happens when you age? • http://www.youtube.com/watch?v=qNf9nzvnd1k • http://www.youtube.com/watch?v=VxcbppCX6Rk

More Related