Just a few questions - calculating the average speed and John's speed

AI Thread Summary
Calculating average speed involves finding the total distance traveled divided by the total time taken, while John's speed is determined as a weighted mean of his speeds across different segments of his journey. To find displacement on a distance-time graph, you consider the overall change in position, not just the sum of distances traveled in each segment. The total displacement is calculated by taking the final position minus the initial position. Clarification on these concepts is essential for understanding the differences in the questions posed. The discussion highlights the importance of accurately interpreting distance and speed in physics problems.
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Normally I would ask my teacher, but since we had the day off and it's due the day we get back, I can't question him.

Homework Statement


What is the difference between calculating the average speed and John's speed (questions g and f)? and how do you find displacement for a distance-time graph (question f), do you just add all the sections where John is moving or do you do the whole journey?


Homework Equations


Speed = distance divided by time.
Displacement = velocity multiplied by time.


The Attempt at a Solution


I have only attempted f, because I just want to the know the difference between question g and f.
25+7=32-32=0.

Thanks in advance.
 
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In g, john's speed is the weighted mean of his speed in the different parts of his journey.
In h, john's average speed in the whole journey is the total displacement divided by the time of the journey.
 
LeonhardEu said:
In g, john's speed is the weighted mean of his speed in the different parts of his journey.
In h, john's average speed in the whole journey is the total displacement divided by the time of the journey.

Thank you for clearing up the difference, it is definitely appreciated.
 
You could have posted an upright image.My head is broken now. :cry:
 
adjacent said:
You could have posted an upright image.My head is broken now. :cry:

I'm sorry, I thought it was upright when I took it, but I think Tinypic must of changed it. :cry:
 
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