1. The problem statement, all variables and given/known data A sled is pulled at a constant speed over a horizontal surface where the kinetic coefficient of friction is .20. What is the minimum force necessary to keep the sled moving if its mass is 2 slugs? 2. Relevant equations f(s)=U(s)N or f(s)=Ns(mg) F(s)= Frictional Force m=weight g=gravity (Not sure about this equation or problem) 3. The attempt at a solution F(s) = Ns(mg) F(s) = (.20)(2 slugs)(32 ft/s^(2)) F(s) = 12.8 N ??? Am I doing this right or wrong? Can somebody please show me how to do this?