A skier slides horizontally along the snow for a distance of 27 m before coming to rest. The coefficient of kinetic friction between the skier and the snow is ľk = 0.050 Initially, how fast was the skier going?
m/s
not sure how to reach the answer with so few variables involved.
equations i thought i might use were: vf = sqrt((2 * (KE) / m)
and KE = 1/2*(m * v^2)
thanks for any extra help.
The work done by friction is
Since the friction force is in the opposite direction to the displacement we have
Now
So what's the normal force? Again we solve this using a Free-Body Diagram. In this case the answer is simple: , thus
Now, the skier starts with a speed . At the end, the skier is at rest, so v = 0 m/s. Thus
So finally we have:
which you can solve for .
-Dan