What must be present for the propagation of a mechanical wave?
Welcome to PF,
What do you think must be present?
I have no idea... Movement?
Hmm, not really what I had in mind. Can you give some examples of a mechanical wave?
P.S. You could have your answer in under five seconds from Google.
sound, earthquake, water waves.... it is vibration?
Correct! Can you now give me examples of non-mechanical waves?
I also read about a medium.
That's the answer Mechanical waves require a medium through which to be transmitted, whereas non-mechanical waves require no medium.
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