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Homework Help: Average acceleration = inst accleration ?

  1. Sep 10, 2004 #1
    Can the average acceleration of a body be not equal to the instantaneous acceleration for at least an instant?

    I know the answer to the question above is NO. But I find the answer; using Mean value theorem in calculus.
    Let me know if there is any answer based on physics.
  2. jcsd
  3. Sep 10, 2004 #2
    What is the meaning of ' average' ?
  4. Sep 10, 2004 #3


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    Let v1=At for a time t1
    then v2=Bt+At_1 for an additional time t2.
    Then a1=A and a2=B.
    However, the [time-weighted] average acceleration is
    aavg= (a1t1+a2t2)/(t1+t2)=(At1+Bt2)/(t1+t2).
    Last edited: Sep 10, 2004
  5. Sep 10, 2004 #4

    Sorry, I don't see any relation between your answer and my question.
    I meant in a given time interval is it possible for a body to has average acceleration 'a' but never reach it as instantaneous acceleration.
  6. Sep 10, 2004 #5


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    II'm not sure what question your asking, but within in a given inertval there will always be an instant when the acceleration is equal to the avergae accelartion within that inertval as long as there are no discontinuities in the accelartion as a function of time within that interval.
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