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B What is a clock?

  1. Dec 10, 2017 #101
    Is this the question you want me to answer? Rather offensive actually. You imply that aside from being ignorant (which I admit) I am also stupid.

    What I have been trying to ask is inertia a factor in the stability of clocks? It is in my pendulum clock, my balance wheel watch and in the stability of the orbital period of the Earth. Does it apply to Atomic clocks? Or other clocks?

    I also asked this about the speed of clocks. Never got an answer.
  2. Dec 10, 2017 #102


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    Inertial mass is not a factor in the tick rate of a light clock.

    Or, to put it differently, inertial mass is as much a factor in the tick rate of a light clock as it is in the length of a ruler.
  3. Dec 10, 2017 #103


    Staff: Mentor

    This is not acceptable. I never said nor implied any such thing, nor did I even think it.

    You are asking a question about a broad topic using non standard terminology and it appears that the responses have been unsatisfactory to you. There are two possibilities, one is that your question was correctly understood and you just don’t like the answer, and the other is that your question has not even been understood so the responses have been responding to misinterpretations of your question. I believe that second possibility is the case here.

    The proper thing to do in that second case is to ask for clarification. To challenge the questioner to address their unspoken assumptions and express the meaning behind their terminology. That is a correct intellectual approach, to which you have twice responded exceptionally emotionally.

    You have not been bullied, nor cut off, not called ignorant, nor stupid. You have been asked for clarification and asked to examine and express the meaning of your question. Instead of responding substantively and helping to clarify your question, you have inaccurately assigned very negative motives to me and avoided the question.
  4. Dec 10, 2017 #104


    Staff: Mentor

    In what way is inertia a factor in a pendulum clock? A pendulum clock has mass, but its frequency does not depend on its mass. So are you asking about the color of the car or the engine of the car?

    A light clock also would have mass, but its frequency would be independent of the mass. So is that all you mean by “inertial factor”, does merely having mass qualify or is there a further qualification implied by your terminology. If so, what is that qualification?

    I don’t think that is a correct statement of the equivalence principle. Roughly the equivalence principle says (with some qualifiers) that gravity is equivalent to acceleration. But acceleration is not the same as inertia, so I wouldn’t say that gravity is equivalent to inertia.
  5. Dec 10, 2017 #105


    Staff: Mentor

    @Torog, please moderate your language. You are very close to a warning. @Dale is trying to help you.

    As both @Dale and @jbriggs444 have responded, the answer is no.
  6. Dec 12, 2017 #106
    At least I got this about atomic clocks which had previously been excluded by other posts.

    @Peter thanks for the warning of a warning!
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