Question

How does heat differ from temperature?
Temperature is the measure of heat.
Temperature and heat are the same thing.
Temperature measures thermal energy, and heat is the flow of thermal energy.
Temperature measures the loss of energy, and heat measures the gain of energy.

Answer 1

Correct choice: "Temperature measures thermal energy, and heat is the flow of thermal energy." (Best phrasing: temperature measures how hot something is — related to the average kinetic energy of its particles — while heat is energy transferred because of a temperature difference.)

Key differences, briefly:
- Temperature is an intensive property that indicates the average kinetic energy per particle (e.g., for an ideal monatomic gas ⟨KE⟩ = (3/2)kBT). Units: kelvin (K), °C, °F.
- Heat (Q) is energy in transit due to a temperature difference; it is an extensive quantity measured in joules (J). Heat is not something an object “has” in equilibrium — it is energy transferred into or out of a body.
- Thermodynamic distinction: temperature is a state property (depends only on the state), heat is a path-dependent quantity (depends on how the change is made).
- Practical relation: when you add heat Q to a mass m with specific heat c, the temperature change is ΔT = Q/(mc) (for simple cases).

Wrong statements:
- "Temperature is the measure of heat" — incorrect: temperature is not the same as the amount of heat.
- "Temperature and heat are the same thing" — incorrect for reasons above.
- "Temperature measures the loss of energy, and heat measures the gain of energy" — incorrect/misleading: both gain or loss of energy can be described by heat flow direction depends on sign; temperature itself is not a measure of gain or loss.