2. LEFT CLICK OR PRESS SPACE BAR TO ADVANCE, PRESS P BUTTON TO GO BACK, PRESS ESC BUTTON TO END LEFT CLICK OR PRESS SPACE BAR TO ADVANCE, PRESS P BUTTON TO GO BACK, PRESS ESC BUTTON TO END COMPUTER PRESENTATIONS FOR KS3 SCIENCE - PHYSICS ©2003, STEVE PARKER COMPUTER PRESENTATIONS FOR KS3 SCIENCE - PHYSICS ©2003, STEVE PARKER

3. 1 1 KS3 SCIENCE - PHYSICS KS3 SCIENCE - PHYSICS Sound

4. SPEED OF SOUND 2 2

5. 3 3 Sound waves are caused by vibrating objects Sound waves are caused by vibrating objects

6. SPEED OF SOUND 4 4 Sound travels through air at a speed of 330 m/s Sound travels through air at a speed of 330 m/s

7. SPEED OF SOUND 5 5 Sound travels through air at a speed of 330 m/s Sound travels through air at a speed of 330 m/s But sound travels at different speeds through different substances, e.g. the speed through water is 1400 m/s But sound travels at different speeds through different substances, e.g. the speed through water is 1400 m/s

8. SPEED OF SOUND 6 6 Sound travels through air at a speed of 330 m/s Sound travels through air at a speed of 330 m/s However, there is no sound at all in a vacuum, since there is nothing to carry the sound wave However, there is no sound at all in a vacuum, since there is nothing to carry the sound wave

9. FREQUENCY & PITCH 7 7

10. 8 8 Sounds may be low pitched or high pitched Sounds may be low pitched or high pitched

11. FREQUENCY & PITCH 9 9 Pitch depends on the frequency of sound waves Pitch depends on the frequency of sound waves

12. FREQUENCY & PITCH 10 Pitch depends on the frequency of sound waves Pitch depends on the frequency of sound waves Fast vibrations create a high frequency and a high pitch Fast vibrations create a high frequency and a high pitch Slow vibrations create a low frequency and a low pitch Slow vibrations create a low frequency and a low pitch

13. AMPLITUDE & LOUDNESS 11

14. AMPLITUDE & LOUDNESS 12 Sounds may be quieter or louder Sounds may be quieter or louder

15. AMPLITUDE & LOUDNESS 13 Volume depends on the amplitude of waves Volume depends on the amplitude of waves

16. AMPLITUDE & LOUDNESS 14 Volume depends on the amplitude of waves Volume depends on the amplitude of waves Smaller vibrations create a low amplitude, so quiet volume Smaller vibrations create a low amplitude, so quiet volume Bigger vibrations create a high amplitude, so loud volume Bigger vibrations create a high amplitude, so loud volume

17. ECHOES 15

18. ECHOES 16 Sound waves will bounce off walls to give an echo Sound waves will bounce off walls to give an echo

19. ECHOES 17 The echo is heard after a delay because it takes time for the sound to travel to the wall and back again The echo is heard after a delay because it takes time for the sound to travel to the wall and back again

20. ECHOES 18 Marine animals and naval ships use echo-location, or “Sonar” to find things Marine animals and naval ships use echo-location, or “Sonar” to find things

21. ECHOES 19 Marine animals and naval ships use echo-location, or “Sonar” to find things Marine animals and naval ships use echo-location, or “Sonar” to find things

22. ECHOES 20 Knowing the speed of sound through water, we can calculate how far away the object is Knowing the speed of sound through water, we can calculate how far away the object is