Final answer:
To keep an engine cool, water is circulated through the engine to absorb excess heat and then passed through a radiator to dissipate the heat into the surrounding air. This cycle helps maintain the engine at a safe operating temperature during hot weather.
Step-by-step explanation:
To keep an engine cool in hot weather, the most common method is the use of water in a car's cooling system due to its high capacity for absorbing heat. As the engine operates, the water circulates through the engine block, absorbing excess heat. In this process, the heat is transferred from the engine to the water. Then, the heated water is passed through the radiator, where it releases the heat to the surrounding air, aided by a cooling fan and the exterior environment. The now-cooled water then recirculates back through the engine to continue the cooling cycle.
Another aspect to consider, as noted in various contexts such as refrigerators and heat engines, is that it is impossible for a process to result solely in the transfer of heat from a cooler to a hotter object. Instead, there is a transfer of heat from a hot source (the engine) to a cooler source (the water in the radiator), and vice versa.