An object, previously at rest, slides #9 m# down a ramp, with an incline of #(pi)/3 #, and then slides horizontally on the floor for another #12 m#. If the ramp and floor are made of the same material, what is the material's kinetic friction coefficient?
1 Answer
The frictional coefficient of the surface is given by
Frictional coefficients have no units.
Explanation:
We are not told the mass of the object, but we can just call it
Two forces due to the weight force of gravity on the object's mass are acting while the object is on the slope: a force parallel to the slope,
A third force is also acting, the frictional force, given by
When the object is moving across the flat floor, only the frictional force is acting. In this case,
The object begins and ends its journey at rest. In the mean time, it accelerates while on the inclined plane and decelerates while on the floor.
Its deceleration in the floor will be given by
As I suspected, the mass of the object cancels out. We can find its velocity,
{sigh - trying hard but struggling on this one and sleepy - will return to wrap it up tomorrow}