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What is the phase difference of the oscillation of a tuning fork?

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marked as duplicate by Ben Crowell, Nathaniel, Waffle's Crazy Peanut, Emilio Pisanty, Chris White Jul 5 '13 at 21:52

This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.

It's not 100% clear what you mean. Phase difference could refer to the lag between two quantities at the same point (e.g. position and velocity at one tip) or to the lag between two motions at different points. In either case, presumably you are only interested in the fundamental? And in any event, one always needs to define the zero-point for being in phase, as this is arbitrary. (Is symmetric motion in phase or out of phase? You decide.) – Chris White Jul 4 '13 at 6:43
duplicate of – Ben Crowell Jul 4 '13 at 13:23
@BenCrowell It is certainly the same physics involved, but the answers to that question most don't address the phase of the prongs explicitly. Now, talks explicitly about phase but again it is not a great duplicate. – dmckee Jul 4 '13 at 14:32
@dmckee: I would consider them duplicates because no answer to one can fail to be an answer to the other. – Ben Crowell Jul 4 '13 at 17:15

To my knowledge, they're 180 degrees out of phase - since they're both going outwards and inwards at the same time, at any given moment they're travelling in opposite directions, hence a one-eighty phase difference.

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This is enforced by the handle. Any other component of the initial motion is damped where the handle is held. – dmckee Jul 4 '13 at 14:29

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