Condition for Instantaneous Acceleration = Average Acceleration

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Instantaneous acceleration equals average acceleration only under specific conditions, such as when the motion is constant over a time interval. To determine if they are equal, one must analyze the graph provided, focusing on the behavior of the velocity over time. If the velocity changes continuously and monotonically, the average and instantaneous values may align at certain points. However, they will not be equal throughout the entire interval unless the acceleration is constant. Understanding these conditions is crucial for solving related physics problems.
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Homework Statement



IMG_20180701_220442.jpg
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Look at this graph.Is Instantaneous Acceleration=Average Acceleration here?
Please explain your solution.
What should be done to check whether Average Acceleration=Instantaneous Acceleration?

Homework Equations


Average Acceleration motion equations

The Attempt at a Solution


I know that Average Acceleration = (Final Velocity-Initial Velocity)/Time Interval
I can't proceed further.
I will be thankful for any help!

 

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When a quantity is changing continuously within a time interval its average value is equal to its instantaneous value only once. When a quantity is constant over a time interval, its average value is always equal to its instantaneous value. Does that help? Read the graph.

On edit: Also see correction below.
 
Last edited:
kuruman said:
When a quantity is changing continuously within a time interval its average value is equal to its instantaneous value only once.
... if it is changing monotonically, that is.
 
haruspex said:
... if it is changing monotonically, that is.
Yes, thanks. Instead of "always", I should have said "only at certain times".
 
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