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Kiwi
Sep19-04, 12:21 PM
Hello,

I was wondering if anyone could help me with the following question:

How long does it take for a shoe to drop 75 m from rest? What is the final velocity?

I have that the acceleration is equal to gravity at -9.8 m/s squared and that the distance is 75 m and the intial velocity is zero but I can't get much further than that. Thanks very very much for your time! :smile:

Pyrrhus
Sep19-04, 12:27 PM
Hello,

I was wondering if anyone could help me with the following question:

How long does it take for a shoe to drop 75 m from rest? What is the final velocity?

I have that the acceleration is equal to gravity at -9.8 m/s squared and that the distance is 75 m and the intial velocity is zero but I can't get much further than that. Thanks very very much for your time! :smile:

Look up kinematic equations

Simfish
Sep19-04, 12:28 PM
y = 75 - 4.9t^2.
Solve for y = 0.

Tide
Sep19-04, 02:39 PM
We're all waiting for the other shoe to drop! (Sorry - couldn't resist!)

BTW - I think air drag will be an important factor in this one but I'm sure your textbook isn't interested in that complication.

h8ter
Sep19-04, 04:48 PM
Yea, in most High School Physics text, air resistance is neglected.

Sjuckett848
Sep19-04, 06:17 PM
(Vf)^2=(Vo)^2+2ad

Vf=Final Velocity
Vo=Initial Velocity
a=Acceleration
d=Distance

*This equation does not include air drag

cdhotfire
Sep19-04, 07:10 PM
ya just use the equation mentioned above and you should be able to get the right awnser. :approve: