Which statement about kinetic energy is true?

Which statement about kinetic energy is true?

• A. Kinetic energy increases with mass and speed squared.
• B. Kinetic energy depends only on speed.
• C. Kinetic energy decreases as mass increases.
• D. Kinetic energy is constant for all objects in motion.

Answer: (A)

Kinetic energy is the energy something has because it’s moving, and it’s given by KE = 1/2 m v^2. This shows why both mass and speed matter, with speed having a squared effect. Doubling the speed increases kinetic energy by a factor of four, while doubling the mass doubles it. So the statement that kinetic energy increases with both mass and the square of speed is the best description. For a quick check: a 1 kg object at 2 m/s has 2 J of energy. At 4 m/s the same object has 8 J. If you double the mass to 2 kg at 2 m/s, it has 4 J. This illustrates how both factors contribute and why speed’s square matters. Kinetic energy isn’t just about speed, and it isn’t constant or decreasing with mass. It changes as speed changes, and increasing mass tends to increase it, not decrease it.

Kinetic energy is the energy something has because it’s moving, and it’s given by KE = 1/2 m v^2. This shows why both mass and speed matter, with speed having a squared effect. Doubling the speed increases kinetic energy by a factor of four, while doubling the mass doubles it. So the statement that kinetic energy increases with both mass and the square of speed is the best description.

For a quick check: a 1 kg object at 2 m/s has 2 J of energy. At 4 m/s the same object has 8 J. If you double the mass to 2 kg at 2 m/s, it has 4 J. This illustrates how both factors contribute and why speed’s square matters.

Kinetic energy isn’t just about speed, and it isn’t constant or decreasing with mass. It changes as speed changes, and increasing mass tends to increase it, not decrease it.