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Unread 15-08-2012, 13:59
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Re: Coefficient of Friction Testing

Quote:
Originally Posted by EricVanWyk View Post
Maybe curvature of the gravitational field, but at that point we are back to complaining that the weight of the people moving in the stands are throwing off the accelerometer measurements.

I'm just trying to understand out how much of the spread is due to mismeasuring the angle, and how much is from other sources. As soon as it starts moving, it goes into kinetic friction. So, if you jostle the setup it will start moving before it 'should'. My untested hypothesis is that this thread is focusing too much on the angle, and not enough on things like how quickly you raise the ramp, or how steady your hand is.
I think even under laboratory conditions with expensive test equipment and experienced technicians you would still see a lot of variation regardless of the measurement methods used. Friction is finicky.