What happens to kinetic energy when particles move faster?

What happens to kinetic energy when particles move faster?

• A. It increases, causing temperature to rise.
• B. It decreases.
• C. It stays the same.
• D. It becomes negative.

Answer: (A)

Kinetic energy depends on how fast a particle is moving, since KE = 1/2 m v^2. When particles move faster, their speeds increase, and their kinetic energy rises. In most matter, temperature reflects the average kinetic energy of the particles, so a higher average speed means a higher temperature. So, as motion speeds up, kinetic energy increases and the temperature goes up. Kinetic energy can’t be negative, and if speed changes, KE changes—not stays the same or decreases just because motion is increasing.

Kinetic energy depends on how fast a particle is moving, since KE = 1/2 m v^2. When particles move faster, their speeds increase, and their kinetic energy rises. In most matter, temperature reflects the average kinetic energy of the particles, so a higher average speed means a higher temperature. So, as motion speeds up, kinetic energy increases and the temperature goes up. Kinetic energy can’t be negative, and if speed changes, KE changes—not stays the same or decreases just because motion is increasing.