Enter the normal force (N), the coefficient of friction, and the distance (m) into the calculator to determine the Work Done By Friction. 

Work Done By Friction Formula

The following formula is used to calculate the Work Done By Friction.

Wf = NF * u * D
  • Where Wf is the Work Done By Friction (N-m)
  • NF is the normal force (N) 
  • u is the coefficient of friction 
  • D is the distance (m) 

To calculate the work done by friction, multiply the normal force by the coefficient of friction and the distance.

How to Calculate Work Done By Friction?

The following example problems outline how to calculate the Work Done By Friction.

Example Problem #1

  1. First, determine the normal force (N). In this example, the normal force (N) is given as 150 .
  2. Next, determine the coefficient of friction. For this problem, the coefficient of friction is given as  .75 .
  3. Next, determine the distance (m). In this case, the distance (m) is found to be 30.
  4. Finally, calculate the Work Done By Friction using the formula above: 

Wf = NF * u * D

Inserting the values from above and solving yields: 

Wf = 150 * .75 * 30 = 3375 N-m

FAQ

What is the significance of the coefficient of friction in calculating work done by friction?

The coefficient of friction is a dimensionless scalar value that represents the ratio of the force of friction between two bodies and the force pressing them together. It plays a crucial role in calculating work done by friction because it quantifies how much frictional force is generated for a given normal force. A higher coefficient indicates more frictional resistance, leading to more work done by friction over a certain distance.

How does the normal force affect the work done by friction?

The normal force, which is perpendicular to the contact surface between two objects, directly influences the work done by friction. Since the frictional force is proportional to the normal force (multiplied by the coefficient of friction), an increase in the normal force results in a higher frictional force. Consequently, for a given distance and coefficient of friction, a larger normal force increases the work done by friction.

Can the work done by friction be negative, and what would that imply?

Work done by friction is typically considered positive when it opposes the motion of an object, as it requires energy to overcome this resistance. However, in physics, work can be negative if the direction of the frictional force and the direction of motion are the same. This scenario is less common and might occur in situations where friction helps move an object, such as when using a conveyor belt. In such cases, negative work implies that energy is being transferred to the object by the frictional force, accelerating it rather than decelerating.