The question is a child slides down a slide with a 28 degree incline and at the bottom her speed is precisely half what it would have been if the slide had been frictionless. Calculate the coefficient of the kinetic friction between the slide and the child.
Hi there, I need help with understanding this guy's solution thanks!
The kinetic friction force will be up the slide to oppose the motion.
We choose the positive direction in the direction of the acceleration.
From the force diagram for the child, we have ?F = ma:
x-component: mg sin...