Velocity-Time Graph: Dog's Position

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aatari
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Hi Guys,

I have attempted the question below and would greatly appreciate if I can get some feedback.

A dog's position is recorded in the graph below. Determine the velocity of the dog in all three segments. Sketch the corresponding Velocity-Time Graph. Please See the attached image.

Here are the velocities that I got:

A = 2 m/s
B = 0 m/s
C = -2.42 m/s

Now for the graph that I will make for velocity-time. Do I just use 10, 20, and 28.25 as x-values and then 2, 0, and -2.42 as y-values?
 

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For c, it looks like he moves 15 meters in 6.667 seconds. Edit: -> It looks like it intersects exactly where those two gridlines meet.
 
TomHart said:
For c, it looks like he moves 15 meters in 6.667 seconds. Edit: -> It looks like it intersects exactly where those two gridlines meet.
So you are saying the dog doesn't go all the to 0? So if that's the case is the velocity then 2.27 m/s?
 
aatari said:
Hi Guys,

I have attempted the question below and would greatly appreciate if I can get some feedback.

A dog's position is recorded in the graph below. Determine the velocity of the dog in all three segments. Sketch the corresponding Velocity-Time Graph. Please See the attached image.

Here are the velocities that I got:

A = 2 m/s
B = 0 m/s
C = -2.42 m/s

Now for the graph that I will make for velocity-time. Do I just use 10, 20, and 28.25 as x-values and then 2, 0, and -2.42 as y-values?

upload_2017-2-20_6-12-16.png

aatari said:
Hi Guys,

I have attempted the question below and would greatly appreciate if I can get some feedback.

A dog's position is recorded in the graph below. Determine the velocity of the dog in all three segments. Sketch the corresponding Velocity-Time Graph. Please See the attached image.

Here are the velocities that I got:

A = 2 m/s
B = 0 m/s
C = -2.42 m/s

Now for the graph that I will make for velocity-time. Do I just use 10, 20, and 28.25 as x-values and then 2, 0, and -2.42 as y-values?

The y values are 20 m, 20 m and 0 m, but it is more accurate to read Δx and Δy from the blue triangle.
upload_2017-2-20_6-12-16.png
 
The dog definitely goes to back to y = 0. I am just saying that the point x=26.6666, y = 5 is a lot easier to read than the point at y=0.
 
Ok that is interesting. Thank you guys!
 
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How did you get this number?
C = -2.42 m/s