How Do I Interpret This Graph for Homework?

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Homework Statement



So should i take the area under the graph or something

Homework Equations


And is in the future i Tackle such problems what are the key thing to remember[/B]

The Attempt at a Solution



Tried subtracting the areas no use xd[/B]
 
Attachments
  • Graph of force Fx in newtons against time t in seconds for a toy car; Fx rises from 0 to 4 N, falls to -2 N, then levels off, with four multiple-choice answers listed below.
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sidt36 said:

Homework Statement



So should i take the area under the graph or something

Homework Equations


And is in the future i Tackle such problems what are the key thing to remember[/B]

The Attempt at a Solution



Tried subtracting the areas no use xd[/B]
Well, what do you know about how force relates to the motion of an object?

Trying random things with a graph rarely leads to anything useful, unless you know something about the physics of what is going on.
 
Well i know that Force * time leads to mass delta velocity
 
sidt36 said:
Well i know that Force * time leads to mass delta velocity
And what sort of calculations did you do with this knowledge, using the graph as a source of data?
 
And i have not done integrals. I have to solve it with a 9th graders knowledge
 
sidt36 said:
I added up the areas of the triangle and tapezium
Can you share these calculations?
 
As much as i can do
 
Attachments
  • Handwritten physics working in green, teal, yellow and magenta ink: impulse equation m·Δv, lines such as 8 = Δv1, 2·Δv2, and v2 - v1 = 8, v3 - v2 = -1.5, v3 - v1 = 6.5, followed by the words 'Now I am stuck'.
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sidt36 said:
As much as i can do
Everything looks OK with your calculations, you just need to put them together.

For the first part of the calculation, you are told that the toy car is at rest initially, so this means that v(t) = 0 m/s when t = 0 sec.

What would be the velocity of the car after 4 seconds, using your figures for the change in velocity?

Don't forget to use the mass of the toy car!