Apiece of driftwood moves up and down as water waves pass beneath it. however, it does not move toward the shore with the waves. what does this demonstrate about the propagation of waves through a medium?

the driftwood is moving up and down because the wave is transferring energy to it. there is no transfer of matter because every molecule stays in its horizontal position moving only up and down. had there been a transfer of matter then the drift wood would have moved towards the shore.

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layers of the earth affect the waves and these effects are seen on instruiments such as seimometers