What are waves?
3 marks · NormalExplain how it is possible to listen to a concert live in a stadium but not be physically touched by the sound waves, even though energy is transferred from the speakers to your ears.
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Sound waves transfer energy through the air by making the air particles vibrate. The energy reaches your ear, but the air itself does not move to your ear from the speaker, so nothing physical touches you.
Also accept: Vibrations travel, not air/gas itself
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Marking points
M1 · 1 mark · Identifies that sound is a wave transferring energy.
M2 · 1 mark · Explains that air particles vibrate but are not moved from speakers to ears.
M3 · 1 mark · States or explains nothing physical (matter/air) moves from speaker to listener.
Worked solution
Sound waves make the air vibrate, transferring energy to your ear drum. The air itself does not travel from the speaker to your ear, so nothing physically travels across the stadium to reach you.