Hi again.

Just spoke with Roy who said the constant is so "fine and variable" that it's not worth calculating. :D

Hi. I'm an OT in No. Colorado and have the same question -- how to account for/calculate the friction constant.

My dad (engineer) gave me the formula but we can't use the gauge to get to a constant rate of movement -- too much fluctuation.

Each surface-sled combo needs to have its own constant calculated. I'll call Roy with this question and get back to you all.

- Dona :roll:

Yeah, the force required to push a weight is definitely going to be a fraction of the weight itself (depending on the coefficient of friction - determined by the sled's contact with the floor.). So if your sled has wheels, it'll take barely any force to push it. If it has glue on the bottom, and it's on a rough floor, it might actually take more force to push it (as compared to the mass on the sled!). Yours is probably somewhere in between - wood sled on a carpet or something... I barely recall any of my Physics 101 class, but I think this was one of the things we covered... :)

Thanks so much for responding... Yeah, the amount of force is MUCH less than the weight in the sled. It didn't ever seem right but that's what I remember being the correct procedure...?
Erica

I think you're right- at least that's the way I do it (each mark is 2.5 pounds)- the actual pounds of force is small compared the the weight in the sled. Anyone else?

Anyone?