Calculatin coefficient of friction for a scooter

[besaw212]

Homework Statement

My task is to design a lab in which i can solve for the coefficient of friction for a razor scooter( the little medal kids one). I planned on varying velocities and distance to show that the coefficient remained constant. Does anyone see any improvements that could me made or variables that i should take into account? Thanks a lot!

Homework Equations

I was going to use KE1= W2
.5mv^2=FN X u X d

The Attempt at a Solution

 

[rock.freak667]

Homework Statement

I planned on varying velocities and distance to show that the coefficient remained constant.

If you are going to solve for it, I do not believe it makes sense to show that it remains constant. The only reason I could see for having to show that it is constant is if you keep changing the surface (meaning that you are testing the surface properties and not really the scooter and one surface if you get what I am trying to say).

I suggest that you just go along measuring the distance and time to get the velocities and apply conservation of energy as you have in your relevant equations. If you simplify this equation you can just measure 't' and 'd' and plot an appropriate graph to get the coefficient of friction μ.

 

[besaw212]

Thanks i see what your saying. Just one question about the graph. I'm having trouble deciding what should be on each axis. Would it be a KE vs D or would a mass drop out on each side and you would be left with velocity vs D ?

 

[rock.freak667]

Thanks i see what your saying. Just one question about the graph. I'm having trouble deciding what should be on each axis. Would it be a KE vs D or would a mass drop out on each side and you would be left with velocity vs D ?

Well I think if you measure 'd' and 't' since acceleration will be constant, v=d/t which you can put into 0.5mv²= μF_nd and get 'd' in terms of 't'. The mass will cancel out so your equation should not involve 'm' at all.