When Object 1 came into contact with Object 2, Object 2 got warmer. What can be concluded about the objects before they came into contact with each other?

Thermal energy moves from the warmer object to the cooler one when they come into contact. Since Object 2 got warmer, Object 1 must have been warmer before contact. A higher temperature means its particles had a higher average speed, so the correct choice is “Object 1 had faster-moving particles.”

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