Question

When are objects in thermal equilibrium? *

When they're the same size.
When they're touching.
When they're the same temperature.
When both objects' temperatures have changed by the same amount.

Answer 1

Answer: When they're the same temperature.

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Thermal equilibrium. The condition under which two substances in physical contact with each other exchange no heat energy. Two substances in thermal equilibrium are said to be at the same temperature.