Final answer:
Heat flows from the hotter object to the colder object when they come into contact, resulting in a transfer of thermal energy.
Step-by-step explanation:
When two objects at different temperatures come into contact, a phenomenon known as heat transfer occurs. Specifically, heat spontaneously flows from the object at the higher temperature to the object at the lower temperature. If we label the hotter object as X with temperature Tx and the colder object as Y with temperature Ty, and Tx > Ty, then the thermal energy loss from object X is the gain of thermal energy by object Y.