Sound lesson 1.pptxccccccccccccccccccccc

Describing that sound is a form of wave, and characteristics of sound waves.
Amplitude, wavelength, frequency, pitch

1. Learning Objectives To be able to describe how sound is produced & travels. To be bale to explain why the speed of sound is different in different materials. To be able to contrast the speed of sound & speed of light.

2. What causes sound? The tuning fork vibrates and you hear a sound. Sounds are made when an object vibrates. Take a tuning fork and strike it against a block of wood. What do you observe? Sound travels because the vibrating object makes nearby particles vibrate. Sound needs a medium to travel through – it cannot pass through a vacuum.

3. Good vibrations! What vibrates so that each of these objects makes sound? harp strings lute strings drum skin

4. How does sound travel through the air?

5. Sound waves need particles to travel through (12) Sound Needs a Medium to Travel – YouTube

6. Sound needs a substance through which to travel because it travels by making particles vibrate. Sound in different materials Which state of matter does sound travel fastest through? The particles in a solid are closer together than in a gas, and more tightly bound than in a liquid. This means vibrations are more easily passed from particle to particle, and so sound travels faster. Sound waves travel fastest through solids.

7. Speed of Sound

8. Which of these travel faster than the speed of sound in air? Breaking the sound barrier The jet fighter and the meteorite travel faster than the speed of sound in air. This is called Supersonic , breaking the sound barrier 120 600 small aeroplane jet fighter cheetah meteorite Distance (m) 5 Time (s) Speed (m/s) 900 50 10,000 2 2.5 0.35 450 20 28,571.4

9. Which comes first?

10. Light does not need a medium to travel through Light travels to earth from the sun through outer space/vacuum where there are no particles!!