SOUNDS GOOD! From musical boxes to iPods

2 Space Walk Aug 2005 Stephen Robinson outside Discovery NASA picture

3 Can he call to those inside the space ship as he works? NASA picture

4 Connected to the space ship by a line Why? NASA picture

5 Lets play some games !

6 Sound dance The bunches move along the line. The children do not move along! Sound moves this way steps

7 Sound travels to your ear The air vibrates but does not travel from the alarm to the ear. Sound

8 Large ears to collect sound Our ears are on the side of our heads. We can play a game to find out why.

9 ? Why does Mittens look unhappy?

10 Whales sing to each other. Sound travels through water.

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12 Bush telephone game Sound travels through the string

13 Telephones -- Are like a sound system The electrical signal is amplified A microphone changes sound to an electrical signal. A loudspeaker changes the electrical signal to sound.

14 Telephones -- The message travels through miles of wires as an electrical signal. microphone loudspeaker electrical signal

15 Radio signal Mobile phones use radio Sound - electrical signal - radio signal - electrical signal - sound In one phone the sound is changed into an electrical signal then into a radio signal. Sound - electrical signal - radio signal - electrical signal - sound In the second phone the radio signal is changed into an electrical signal then into sound. Mobile phone beacons

16 What is this? What sound does she make?

17 What are these? What sound do they make?

18 What sound does this make? How does it make the sound?

19 Bells What sounds will they make?

20 Straw oboes Listen as the straw is snipped. blow

21 Size matters! Large things make ___________ sounds Small things make ___________ sounds

22 New words: High pitch = high frequency Low pitch = low frequency

23 Size matters!

24 What else changes sounds? How do you tune a violin? Let us try to make a string instrument.

25 What have we learned? Vibrating objects make sounds Sound needs a medium through which to travel – air, water, string The medium vibrates but does not travel with the sound Large vibrations make loud sounds - small vibrations make quiet sounds Large objects make low frequency sounds - small objects make high frequency sounds In strings the frequency of the sound depends on the length, thickness, and tension.

26 Can you spot the baby? Sound has lots of uses

27 Ultrasound is very, very high frequency sound. It is used to see inside people - to see babies before they are born if a heart is working well blood flow

28 Knowledge about sound helps - Musical instrument design and playing them Sailors find how deep the water is Building design so we hear sounds clearly in meetings so sound does not travel through walls Sound systems for everyone radio - CD players mobile phones - iPods

29 Physics is everywhere From kittens ears to mobile phones