1. Sound Energy Cian Taylor Email: cian.taylor@ireland.com
Web:

2. Energy Energy is the ability to do work.
You can think of energy as the ability to move something.

3. Sound is a Form of Energy
A table tennis ball hung in front of a speaker
Ball will move as the sound waves hit it.
Table-tennis
ball
Sound waves

4. Sound as a Form of Energy
Sound Energy

5. Conversion of Sound Energy
Sound causes our eardrums to vibrate.
This is an example of sound energy being converted from one form of energy to another, mechanical energy. Both forms are kinetic energy.

6. Conversion of Sound Energy
Click on each box below to see how
- sound energy is converted to kinetic energy
- and to electrical energy

7. Conversion of Sound Energy
Sound energy is converted into electrical energy in a telephone.
How?
The sound energy is converted to electrical energy by a microphone. Then into radiant energy when it is sent to the other phone.

8. Conversion of Sound Energy
At the other end of the phone line
The radiant energy is converted back to electrical energy which is converted back into sound energy.

9. Sound Transmission
Transmission means sending from one place to another.
Sound waves are transmitted by particles in the air.
Animation courtesy of Dr. Dan Russell, Kettering University
Air Molecules
Ear
Speaker

10. Sound Transmission in Air
Sound waves in air are passed between molecule
What happens when you change frequency above?

11. Sound does not Travel in a Vacuum
A java applet is embedded in this slide, click to activate it.
Click on the graphic above to start the simulation.

12. The Speed of Sound The speed of sound in air is about 340 m/s.
So every second, a sound wave travels 340 metres.
Sound travels at different speeds in different materials.

13. The Speed of Sound
Sound travels at different speeds in different materials.
In air m/s
In water m/s
In steel m/s

14. The Speed of Sound
Which is faster, the speed of light or the speed of sound?
How do you know?

15. The Speed of Sound The speed of light is much faster!
The speed of light ,000,000 m/s
(approximately 186,282 miles per second )
The speed of sound in air m/s
(0.21 miles per second)

16. Light and Sound Fireworks: Waves on a beach: Lighting:
- you see the firework explode before you hear the bang.
Waves on a beach:
- you’ll see the waves break before you hear them breaking.
Lighting:
- you see the lightning
before you hear the thunder.