Written by the Fiveable Content Team • Last updated September 2025
Verified for the 2026 exam
Verified for the 2026 exam•Written by the Fiveable Content Team • Last updated September 2025
Definition
Non-conservative forces are external forces that do work on an object, causing a change in its mechanical energy. These forces depend on the path taken by the object and can result in energy being transferred to or from the system.
Friction is a common example of a non-conservative force. It opposes the motion of objects sliding against each other, converting kinetic energy into thermal energy.
The work-energy principle states that the net work done on an object equals its change in kinetic energy. Non-conservative forces contribute to this net work, altering an object's kinetic energy.
Air Resistance: Air resistance is another example of a non-conservative force that acts against the motion of objects moving through air. It converts some of their kinetic energy into other forms such as heat or sound.