Solving Online Motion Problems: Understanding Velocity and Slope

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I'm trying to do an online homework, and I think I have the right answer but every time I put it in it says its wrong :(

Take a look..

This is the graph
Position-time graph with a straight blue line from the origin to time 7 (x4 s) and position 6 (x5 m), with dashed guide lines marking the endpoint. Horizontal axis: time (x4 s), 0 to 9. Vertical axis: position (x5 m), 0 to 6.


and then the question is:
What velocity is represented by the graph?
Answer in units of m/s.

I keep putting 1.25m/s because 5/4=1.25 so that's the slope, and the velocity right?

Any help will help.
thanks.
 
sickphysic said:
I'm trying to do an online homework, and I think I have the right answer but every time I put it in it says its wrong :(

Take a look..

This is the graph
Position-time graph of a straight line from the origin to (7, 6) with a blue line and dashed guides; the vertical axis is position (×5 m) from 0 to 6 and the horizontal axis is time (×4 s) from 0 to 9.


and then the question is:
What velocity is represented by the graph?
Answer in units of m/s.

I keep putting 1.25m/s because 5/4=1.25 so that's the slope, and the velocity right?

Any help will help.
thanks.

Where are you getting the slope as 5/4?

First, you will need to multiply out the units on each axis. I don't know why they did it so strangely, but whatever. Re-label the graph in meters and seconds (applying the multiplication factors shown for each axis), and then figure out the rise/run of the graph.
 
I'm getting the 5/4 cause if each division on the y-axis is 5, and then each division on the x-axis is 4 then the slope is 5/4?
Isn't it?
 
sickphysic said:
I'm getting the 5/4 cause if each division on the y-axis is 5, and then each division on the x-axis is 4 then the slope is 5/4?
Isn't it?

Multiply each number on the vertical scale by 5. So instead of being 1, 2, 3, ... it's 5, 10, 15,...

Do the similar thing for the horizontal axis. Now it is re-labelled. Now look at how the line starts at (0,0) and goes up to (?,?). That should give you the slope of the line...
 
This is what you're saying right?

Position versus time graph with a straight blue line from the origin rising to 6 on the vertical axis at 7 on the horizontal axis; axes labelled position (×5 m) and time (×4 s), with dashed guide lines.


so doesn't that make the slope 5/4?
 
I got it! lol
I didn't realize that the line didn't cross exactly at the 5,4 point but the 6,7 instead.
thanks (: