What are waves?
2 marks · NormalA loudspeaker produces sound waves that pass through the air. Explain, using scientific ideas, why the air itself does not move from the loudspeaker to your ear.
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The sound wave travels by vibrating air particles back and forth (oscillations) without the particles themselves moving from the loudspeaker to your ear; it is energy, not matter, that is transferred.
Also accept: Air particles only vibrate back and forth, they do not travel all the way from the loudspeaker to the ear.; The movement of energy happens as vibrations pass from one particle to the next.
Common mistakes: Saying air moves to your ear; Describing matter transfer instead of energy transfer
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Marking points
B1 · 1 mark · States that air particles vibrate or oscillate, but do not travel from source to ear.
B2 · 1 mark · Mentions that energy is transferred, not matter.
Worked solution
In sound waves, air particles vibrate about their fixed positions (oscillate), transferring energy from one particle to the next, but they do not make a journey from the loudspeaker to your ear.
The wave transfers energy, not matter.