- #1

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I know the impulse is the area under the curve....

[tex]mv_{1} + F_{avg}\Delta{t} = mv_{} [/tex]

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- Thread starter Jason03
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- #1

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I know the impulse is the area under the curve....

[tex]mv_{1} + F_{avg}\Delta{t} = mv_{} [/tex]

- #2

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What is the force of friction?

What is the impulse of friction?

How does that change your equation?

What is the impulse of friction?

How does that change your equation?

- #3

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This equation allowed me to come up with the correct answer

[tex] mv_{1} + P-T(\Delta{t}) = mv_{2}[/tex]

- #4

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Im having trouble coming up with velocity for Time at 8 seconds.....I came up with the Velocity at 5 seconds easily using the equation above.....

heres the graph for the problem....http://img91.imageshack.us/img91/6935/graphmp3.jpg [Broken]

im trying to find the average Force at T = 8 seconds.....but its not working

heres the graph for the problem....http://img91.imageshack.us/img91/6935/graphmp3.jpg [Broken]

im trying to find the average Force at T = 8 seconds.....but its not working

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- #5

Doc Al

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- #6

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I used this equation to solve for time at 5 seconds....and it worked...

[tex] mv_{1} + P-T(\Delta{t}) = mv_{2}[/tex]

but I tried solving for time at 8 seconds... finding the area under the curve which is just a rectange and triangle...but the answer comes up incorrect

as far as area it should just be [tex](L * W) + (.5*b*h)[/tex]

[tex] mv_{1} + P-T(\Delta{t}) = mv_{2}[/tex]

but I tried solving for time at 8 seconds... finding the area under the curve which is just a rectange and triangle...but the answer comes up incorrect

as far as area it should just be [tex](L * W) + (.5*b*h)[/tex]

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- #7

Doc Al

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That equation is not quite right. That second term (P) is a force, not an impulse. (It should be the area under that curve.)I used this equation to solve for time at 5 seconds....and it worked...

[tex] mv_{1} + P-T(\Delta{t}) = mv_{2}[/tex]

Looks fine to me. Show me the details. What did you get for the impulse due to the force P? The impulse due to the friction force T?but I tried solving for time at 8 seconds... finding the area under the curve which is just a rectange and triangle...but the answer comes up incorrect

as far as area it should just be [tex](L * W) + (.5*b*h)[/tex]

- #8

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Don't forget that Impulse is NET force * time. So if you have the graph of the force of the engine vs. time, you need to subtract out kinetic friction, which is considered constant over the time.

If the MR2 that kept up well with the viper was a Spyder, that is I think 137 hp and not 115 hp.

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