1. The problem statement, all variables and given/known data There is a string that is attached to a bar as shown below in the picture. What is the coefficient friction between the bar and floor before bar starts slipping. Reference https://www.physicsforums.com/threa...t-of-friction-using-torque-and-forces.723351/ 2. Relevant equations Moment which is moment (torque) = F r (position) 3. The attempt at a solution I have chosen a pivot point about the point where the bar contacts with the ground. The equation for the torque about the point where bar contacts with the ground -> - mg *1.4863 - T*1.814989 = 0 I found 1.814989 by using the cross product. Then Fx = 0 -Tsin21 - f(friction) = 0 -Tsin21 - u(coefficient of friction) *N = 0 Fy = 0 -mg + N + T*cos21 = 0 Now, i'm stuck and i don't how to proceed further. Also, i'm confused about this part -> So the formula for friction is f = u*N, is N equals to mg ?