Hot air _____________ and cold air _____________ due to ___________.
*
1 point
falls; rises; gravity
rises; falls; gravity
rises; falls; bouyancy
falls; rises; bouyancy
rises; falls; bouyancy
Hot air rises and cold air falls due to buoyancy.
To understand why hot air rises and cold air falls, we need to consider the concept of buoyancy. Buoyancy is the upward force exerted on an object immersed in a fluid (in this case, air) and it depends on the difference in density between the object and the fluid.
The air around us is a fluid, and it becomes less dense as it is heated and more dense as it is cooled. When air is heated, it expands and becomes less dense than the surrounding cold air, causing it to rise. This is because the less dense hot air creates an upward buoyant force that is greater than the downward force of gravity. As a result, hot air rises above the colder air.
On the other hand, when air is cooled, it contracts and becomes more dense. The denser cold air then displaces the less dense warm air, causing it to fall. This is also due to buoyancy – the denser cold air creates a greater downward force compared to the upward force of the less dense warm air, causing it to descend.
So, in summary, hot air rises and cold air falls due to the buoyant forces created by the density differences between the hot and cold air masses.