1. A curling stone with a mass 20.0kg leaves the curler's hand at a speed of 0.885m/s. It slides 31.5m down the rink before coming to rest. Find the average force of friction acting on the stone. 2. So far I have (I think) net force, acceleration, average velocity and time. I need either the force of friction, or the force applied to work out the force of friction. 3. So far my combined formula looks like this, have not put any numbers in yet. Fnet = [m(V2-V1)(V1+V2)]/2d.