Which term describes energy due to an object's motion?

Which term describes energy due to an object's motion?

• A. Potential energy
• B. Thermal energy
• C. Chemical energy
• D. Kinetic energy

Answer: (D)

Energy due to motion is called kinetic energy. It depends on how heavy the object is and how fast it’s moving, expressed by the formula KE = 1/2 m v^2. This means that doubling the speed has a big effect because velocity is squared, and a heavier object at the same speed has more energy as well. For example, a 2 kg object moving at 3 m/s has KE = 1/2 × 2 × 3^2 = 9 joules; if it speeds up to 6 m/s, its KE becomes 1/2 × 2 × 6^2 = 36 joules, four times as much. This concept helps explain everyday motion: a moving car, a thrown ball, or a rolling skateboard all store energy in their motion. Other energy types describe different situations: potential energy is energy stored due to position (like a book held above the ground); thermal energy relates to temperature and the microscopic motion of particles; chemical energy is stored in bonds between atoms and can be released in reactions. Energy can move between these forms as objects move and interact, but the energy tied specifically to movement is kinetic energy.

Energy due to motion is called kinetic energy. It depends on how heavy the object is and how fast it’s moving, expressed by the formula KE = 1/2 m v^2. This means that doubling the speed has a big effect because velocity is squared, and a heavier object at the same speed has more energy as well. For example, a 2 kg object moving at 3 m/s has KE = 1/2 × 2 × 3^2 = 9 joules; if it speeds up to 6 m/s, its KE becomes 1/2 × 2 × 6^2 = 36 joules, four times as much. This concept helps explain everyday motion: a moving car, a thrown ball, or a rolling skateboard all store energy in their motion.

Other energy types describe different situations: potential energy is energy stored due to position (like a book held above the ground); thermal energy relates to temperature and the microscopic motion of particles; chemical energy is stored in bonds between atoms and can be released in reactions. Energy can move between these forms as objects move and interact, but the energy tied specifically to movement is kinetic energy.