Average acceleration = inst accleration ?

AI Thread Summary
Average acceleration cannot differ from instantaneous acceleration at any point within a given time interval, provided there are no discontinuities in acceleration. The Mean Value Theorem in calculus supports this by indicating that there will always be an instant where the instantaneous acceleration equals the average acceleration over that interval. The discussion emphasizes the definitions of average and instantaneous acceleration, clarifying their relationship. The mathematical representation of average acceleration is also highlighted, reinforcing the concept. Overall, the consensus is that average and instantaneous accelerations align at some point during the interval.
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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.
Thanks
 
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What is the meaning of ' average' ?
 
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:
robphy said:
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).


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.
 
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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