Which is an example of potential energy?

• A. Water stored behind a dam.
• B. A parked car.
• C. A light bulb lit.
• D. A swinging swing.

Answer: (A)

Potential energy is the energy stored because of an object's position in a gravitational field. Water stored behind a dam sits at a height above the downstream area, giving it gravitational potential energy. This energy can be released as water flows downward through turbines, converting into kinetic energy and then electrical energy. The other options show energy in use or in motion rather than stored: a parked car on level ground has little stored energy, a lit light bulb is using electrical energy rather than storing it, and a swinging swing has energy continually swapping between potential and kinetic as it moves, not simply stored energy ready to be released. So, water behind a dam is the best example of potential energy.