Convection happens when heat is transferred by a current in air or liquid. It is what happens in boiling water, hot air balloons, the ocean and even in the magma under Earth’s surface. When air or liquid warms, the molecules move faster and get less dense. They rise, and the denser, cooler air or liquid sinks. As the cooler air or liquid nears a heat source—like a lit stove or the Earth’s core—it warms and rises. The cycle continues. One way people use convection is in heating and cooling their homes. In cooler climates, like the Northeast region of the United States, people turn on the heat more often than the air conditioning. In these homes, air vents are usually near or on the floor. When hot air comes out of the vents, it rises and fills up the room with warmth. Since homes in cooler climates use the vents for heat more often than cooling, it makes the most sense to have the air vents near the floor.
Based on the passage, where would you most likely find air vents in a home in a very hot climate?
A
nowhere because hot climates don’t need air vents
B
near the center of a wall
C
near the ceiling
D
near the floor