Non-conservative forces

Definition

Non-conservative forces are forces where the work done depends on the path taken. Examples include friction and air resistance, which convert mechanical energy into heat or other forms of non-recoverable energy.

5 Must Know Facts For Your Next Test

1. Non-conservative forces cause a change in the total mechanical energy of a system.
2. They cannot be described by a potential energy function.
3. Work done by non-conservative forces is path-dependent.
4. Friction and air resistance are common examples of non-conservative forces.
5. In the presence of non-conservative forces, the principle of conservation of mechanical energy does not hold.

Review Questions

• What distinguishes non-conservative forces from conservative forces?
• How do non-conservative forces affect the total mechanical energy of a system?
• Give two examples of non-conservative forces and explain their effects on motion.

Related terms

Conservative Forces: Forces for which the work done is independent of the path taken and can be fully recovered, such as gravity and spring force.

Mechanical Energy: The sum of kinetic and potential energy in a system. Non-conservative forces can change it by converting it into other forms like heat.

Potential Energy: Energy stored in an object due to its position or configuration. Only conservative forces have associated potential energies.