1. Mrs. Trotter’s Science Class Chapter 4 Waves, Light, sound
How the ear works
Mrs. Trotter’s Science Class
Chapter 4 Waves, Light, sound

2. The Ear The Outer Ear The Middle Ear The Inner Ear
cup shaped to collect sound waves
The Middle Ear
sound waves hit against the ear drum causing it to vibrate, then transmitting them to tiny bones
The Inner Ear
fluid filled chambers called cochlea. Tiny hairs will pick up waves and produce nerve signal to be sent to the brain

3. The Human Ear

4. Sounds a type of wave that can be heard longitudinal mechanical waves
must travel through a medium

5. Hearing ranges
Young healthy humans can hear sound waves produced by vibrations with frequencies between about 20 Hz and 20,000 Hz
As people age, the ability to hear the higher and lower frequencies of sound decrease

6. Hearing by age

7. Animals have ranges that help them catch prey Dog- 15-50,000 Hz
Dolphin ,000 Hz
Mice 1,000-91,000 Hz

8. How much is a Hz?
How old are your ears?

10. Compressions
the region on the longitudinal wave where the particles of the medium are closest together

11. Rarefactions
the region on the longitudinal wave there the particles are farthest apart

12. Pitch The perception of how high or low a sound seems
generally the female voice is higher pitched than a males voice

13. Decibels A unit used to measure sound intensity or loudness
whisper 25 decibels
alarm clock 80 decibels
rock concert 140 decibels

14. Too loud?

15. Quiz
Sound waves are compressions and ___________ that move away from a sound source.
Sound waves are produced when an energy source cause matter to _____________.
You hear sounds when your ears capture sound waves and produce signals that travel to your ________________.