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DrummingAtom
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Homework Statement
A truck is moving on a level street with speed Vo when the brakes lock (the tires don't roll and skid). Find the minimum stopping distance of the truck in terms of Vo, g, and the coefficient of kinetic friction μk.
Homework Equations
W = F*d
W = K2-K1
K = 1/2mv2
The Attempt at a Solution
Ok, I think I got this one because want to make sure because when I'm plugging in numbers at the end it seems a little strange.
I started with W = K2-K1 and K2 will be zero because it's stopped at that point.
W = -K1
I took that -g = n and applied it to the left side, was that step right?
-F*d = -K1
-F*d = -1/2mVo2
Solving for d gives:
[tex] d = \frac{-\frac{1}{2}mV_{o}^2}{-m\mu_{k}g}[/tex]
Then after rearranging:
[tex] d = \frac{V_{o}^2}{2\mu_kg}[/tex]
Now here's where I'm a little confused, if what I did was right. How can the final equation not have mass? A semi would certainly take a longer distance to stop than a Geo Metro. That's why this equation is so bizarre to me. I'm guessing this is why my Professor assigned this problem, haha. Thanks for any help.