A boy and his skateboard have a combined mass of 60kg. After an initial shove, the boy starts coasting at 5.5m/s along a lever driveway. Friction brings him to a stop in 5.0 s. If the combined force of gravity on the boy and skateboard is 590 N, what is the average coefficient of (rolling) friction between the driveway and the skateboard wheels?

Greg drew a diagram to compare two of the fundamental forces. which labels belong in the areas marked x, y and z? gravitational force electromagnetic force x. attractive y repulsive z: infinite range x: infinite range y attractive z. repulsive x. always attractive y: infinite range z: attractive or repulsive x. attractive or repulsive y infinite range z: always attractive