How to determine the coefficient of friction by the force of friction and force of reaction of the support?

The friction force is directly proportional to the coefficient of friction and the reaction force of the support, which means that the problem is solved by the formula F = kN (The formula perfectly reflects the direct relationship). Here F is the friction force, N is the support reaction force, k is the friction coefficient. There is a pattern in the formula, N = F / k, k = F / N. That is, to find the coefficient of friction, you need to divide the friction force by the reaction force of the support. Example: F = 6, N = 3. 6 = k * 3, k = 6/3, k = 2. Let’s check that 2 * 3 is really equal to 6, which means the problem has been solved correctly and the pattern has been established correctly.