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ruck101
Oct21-04, 10:53 PM
Here's the problem:

diameter = 3.45 cm
angular speed = 11.4 rad/s
angular deceleration = -.96 rad/s

How far does the coin roll before coming to a stop?

How would I set this problem up? Thanks!

Pyrrhus
Oct21-04, 11:02 PM
Remember

v = r \omega

a = r \alpha

ruck101
Oct21-04, 11:08 PM
thanks for the reply.
ok, I converted 3.45 cm to m = .0345 m
then, I got the linear velocity = 11.4 x .0345 = .3933 m/s
next, I got the linear acceleration = -.96 x .0345 = -.03312 m/s^2

ok, I plug all of this into a kinematics equation and get 5.94 m, does this sound right? Thanks!

Spectre5
Oct21-04, 11:12 PM
r is radius....you must change the diameter to radius

ruck101
Oct21-04, 11:15 PM
dang, I did that the first time I tried this..lol. ok let me reattempt this.

ruck101
Oct21-04, 11:18 PM
I get the same exact thing.

ruck101
Oct22-04, 07:38 AM
Anyone.....?