Enter the normal force (N), the coefficient of friction, and the radius (m) into the calculator to determine the Frictional Torque. 

Frictional Torque Formula

The following formula is used to calculate the Frictional Torque.

Tf = N*u*r
  • Where Tf is the Frictional Torque (N-m)
  • N is the normal force (N) 
  • u is the coefficient of friction 
  • r is the radius (m) 

To calculate frictional torque, multiply the normal force, coefficient of friction, and radius together.

How to Calculate Frictional Torque?

The following example problems outline how to calculate the Frictional Torque.

Example Problem #1

  1. First, determine the normal force (N). In this example, the normal force (N) is given as 5 .
  2. Next, determine the coefficient of friction. For this problem, the coefficient of friction is given as  10 .
  3. Next, determine the radius (m). In this case, the radius (m) is found to be 20.
  4. Finally, calculate the Frictional Torque using the formula above: 

Tf = N*u*r

Inserting the values from above and solving yields: 

Tf = 5*10*20 = 1000 (N-m)


Example Problem #2

Using the same method as above, determine the variables required by the equation. For this example problem, these are provided as:

normal force (N) = 10

coefficient of friction = 20

radius (m) = 30

Enter these given values yields: 

Tf = 10*20*30 = 6000 (N-m)