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tiny-tim
#3
Mar9-12, 01:39 PM
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hi iJamJL!
Quote Quote by iJamJL View Post
I think I should be using F=ma, and to find the acceleration, I can take the second derivative of the given formula. However, I forget whether that is allowed in one-dimension. If not, then do I use F=mg?
if you need to find the force, then yes you use F = ma

and yes the acceleration is the second derviative, even in three dimensions!

(what is worrying you about that? )
To find the distance, I plugged in 1.49 into the formula they gave, and I got (-48.5). I know that to find work, the formula is W=F*s, so in order to find the force, I'm not sure which formula to use.
yes, that does give you the total distance

but W = F*s only works if F is constant

here, F isn't constant, so you would have to use W = ∫ F.ds
however it might be simpler to use the work-energy theorem, and calculate the difference in kinetic energy