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HELP! velocity in terms of x...???????? (1 Viewer)

xoxo

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im really confused here....

The velocity of a particle is given by
dx
__ =e ^ -2x ms^-1
dt

if the particle is initially at the origin find the

a) exact time when its displacement will be 1.5
b) its displacement after 5sec...

i could probably do b) but i dont know where to start for a).....

any help??
i have my exam tomoz and am really stressing!
 

SoulSearcher

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If you have dx/dt = some function in terms of displacement, x, etc., then I believe you would flip both sides of the equation, i.e. get dt/dx = 1/some function of x, then integrate with respect to x. So in this question,
dx/dt = e-2x ms-1
dt/dx = 1/e-2x
= e2x
Therefore t = Int. [e2x] dx, then integrate with respect to x.
 

webby234

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Yeah and don't forget the constant of integration.

Sub in t = 0, x = 0 to find its value.
 

webby234

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Haha thanks, I don't actually know - we never got our marks back for it, but I got HD for the course overall. What are you planning to do?

How was the residential?
 

SoulSearcher

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webby234 said:
Haha thanks, I don't actually know - we never got our marks back for it, but I got HD for the course overall. What are you planning to do?

How was the residential?
Nice :uhhuh: Well, dark matter, most likely, since it's the only thing I've got a solid interest in, although all this quantum stuff keeps appearing in the back of my mind every so often :eek:

It was good, real good, lot more sociable since we all already knew each other so it was a blast :D
 

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