A box has mass 13 kg and is at rest on a flat floor. A minimum force of 47 N is needed to push the box so it moves across the floor. What is the coefficient of static friction between the box and floor?
let's call N=Normal force. m*g=Weight. F= Force needed to move the block. f = friction force. k = static friction coefficient. For balance: N = mg and F = f By definition f=k*N. Clearing this last expression: k=f/N. Substituting: k=f/N=F/m*g=(47)/((13)*(9.8))=0.37 the coefficient of static friction between the box and floor is 0.37
