What is temperature?

What is temperature?

• A. The total energy of all particles in the substance.
• B. The average speed of the particles in a substance.
• C. The amount of heat in the substance.
• D. A measure of the average kinetic energy of the particles in a substance.

Answer: (D)

Temperature is a measure of the average kinetic energy of the particles in a substance. When a substance is warmer, its particles, on average, have more kinetic energy and move more vigorously. This energy per particle depends on both how fast the particles move and their mass, which is why temperature isn’t simply the average speed. It’s also not the total energy of all particles, since that depends on how much substance you have, and it’s not heat, which is energy transfer due to a temperature difference. So the correct idea is that temperature reflects the average kinetic energy of the particles in the substance.

Temperature is a measure of the average kinetic energy of the particles in a substance. When a substance is warmer, its particles, on average, have more kinetic energy and move more vigorously. This energy per particle depends on both how fast the particles move and their mass, which is why temperature isn’t simply the average speed. It’s also not the total energy of all particles, since that depends on how much substance you have, and it’s not heat, which is energy transfer due to a temperature difference. So the correct idea is that temperature reflects the average kinetic energy of the particles in the substance.