Explain to me Step Functions for VT graphs

AI Thread Summary
Step functions in velocity-time graphs can be confusing, particularly when interpreting average velocities from distance-time graphs. The discussion highlights that the average velocity from 0 to 6 seconds is 30, but the velocity must increase to 60 at t = 6 to achieve this average, indicating a linear change rather than a step. The confusion arises from the expectation of a step in the velocity graph, which is incorrect if the velocity varies continuously. The key takeaway is that if the velocity changes linearly, the graph will not show a step but rather a smooth transition. Understanding these relationships is crucial for accurately interpreting motion graphs.
kencamarador
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I am sort of confuse about this step functions. In the picture below, the top is the distance time graph and the bottom is velocity time graph. The arrow pointing is what is confusing me. Its not suppose to be a step up (answers in my book) but i calculated the slopes

First curve line = 30
Second straight diagonal line = 60
Second curve line = 35

So I put it in my velocity time graph but the part where the arrow is pointing, isn't that correct though?

But the correct answers show that the first line on the velocity time graph is connected to the horizontal second line.

I am so confuse...

Both graphs have same intervals.

http://imgur.com/52DSmKv

http://imgur.com/52DSmKv
 
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Delphi51 said:
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i posted the link

http://imgur.com/52DSmKv
 
The problem is with the first curved line. The average velocity from 0 to 6 is 30, but the velocity is varying from zero at t = 0 to a value higher than 30 at t = 6, in order for the average to be 30. If the velocity is varying linearly with time in this region, then the velocity at t = 6 has to be 60 in order to the average to be 30. Then there won't be any step.
 
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