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twz06
Aug 28, 2007, 03:17 PM
A bolt comes loose from the bottom of an elevator that is moving upward at a speed of 6.50 m/s. The bolt reaches the bottom of the elevator shaft in 4.55 s. How high up was the elevator when the bolt came loose?

Capuchin
Aug 28, 2007, 11:39 PM
Hi, sounds like one of the suvat equations will do it.

You know a, t, and u and you want to find s. You don't want an equation with v in it though.

Can you identify which one you can use?

twz06
Aug 29, 2007, 05:54 AM
Would you use the equation x=xi+vi(t)+1/2at^2?? I'm still stumped

Capuchin
Aug 29, 2007, 05:56 AM
Erm, I think that's the one.

s = ut+1/2at^2

just plug in the numbers and you get a reasonable looking s

twz06
Aug 29, 2007, 06:04 AM
What stands for "u" I think I have different variables, what is your u??

Capuchin
Aug 29, 2007, 08:53 AM
u is normally initial velocity.

I understand your equation now, yes that's the right one to use.