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Find needed force

  • #1
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3

Homework Statement


upload_2018-9-22_6-10-14-png.png

Looking for F for 200 km/hr

Homework Equations



F=ma

The Attempt at a Solution



F-cv^2 = ma
F= ma +cv^2

v=200 km/hr

F= ma +c(200 km/hr)^2

so now I need to find a, from previous work I found that

t= (m/c)*(1/2 vter)*(ln[ (vter +v)/(vter-v)])

next I would solve for v and take the derivate to get a.

but I know that

v^2 =v0^2+2a( x -x0)

where

a= v^2-v0^2 / 2(x-x0)

I know that v=2000 km/ hr
v0=0 since it was at rest
x= final distance
x0=0 since it starts at the origin
 

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Last edited:

Answers and Replies

  • #2
Charles Link
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  • #3
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Thanks Charles and SammyS.

@Ashley1nOnly What makes you think you will understand what 69 posts before didn't achieve, which btw. is still open?
Thread closed.
 

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