What is kinetic energy?

• A. The energy of motion.
• B. The energy stored in chemical bonds.
• C. The energy due to gravity.
• D. The energy associated with temperature.

Answer: (A)

Kinetic energy is the energy an object has because it is in motion. It depends on both how heavy the object is and how fast it’s moving, following the relation KE = 1/2 m v^2. This means more mass or higher speed gives more kinetic energy, and doubling the speed has a bigger effect because it’s squared. This form of energy is different from chemical energy (stored in bonds) and thermal energy (related to temperature), and from gravitational potential energy (energy due to position in a gravitational field). Gravity can change kinetic energy by accelerating a falling object, converting potential energy into motion energy as it speeds up.