# Homework Help: Average acceleration = inst accleration ?

1. Sep 10, 2004

### Omid

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

2. Sep 10, 2004

### Rogerio

What is the meaning of ' average' ?

3. Sep 10, 2004

### robphy

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
4. Sep 10, 2004

### Omid

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.

5. Sep 10, 2004

### jcsd

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.