Practice question · Fill in the blanks
Complete the statement about what a wave carries.
As water waves pass beneath it, a floating cork ______, because a wave transports energy rather than matter.
Word bank: drifts steadily along with the wave · bobs up and down roughly in place · sinks a little further with each wave · travels backwards against the wave
Hints
- Each point of the medium oscillates about its own equilibrium position.
- If the medium travelled with the wave, an ocean would empty itself onto the beach.
Show the answer
As water waves pass beneath it, a floating cork bobs up and down roughly in place, because a wave transports energy rather than matter.
Why
The medium oscillates locally while the disturbance and its energy move on. This is precisely what separates a wave from a stream of particles: sound carries the energy of a shout across a room without carrying any air across it.
Practise Waves
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