What does kinetic energy describe?

• A. Potential energy stored.
• B. Energy of motion.
• C. Energy due to position.
• D. Energy lost in friction.

Answer: (B)

Kinetic energy describes the energy an object has because it's in motion. It grows with both mass and speed, following the relationship KE = 1/2 m v^2, so doubling the speed has a big effect because velocity is squared.

This isn’t energy tied to position or a configuration—that’s potential energy, the energy stored due to where something is or how it’s arranged. And when we talk about energy lost in friction, that describes a process where moving energy is transformed into heat rather than a separate kind of energy itself. The kinetic energy is what decreases as friction does work on the moving object, not a distinct energy category.