Imagine a special air filter placed in a window of a house. The tiny holes in the filter allow only air molecules moving faster than a certain speed to exit the house, and allow only air molecules moving slower than that speed to enter the house from outside. Explain why such an air filter would cool the house, and why the second law of thermodynamics makes building such a filter an impossible task.
Solution 7DQ Step 1: The special air filter allows the faster molecules to leave the house through window. The average speed of the molecules inside the house gets reduced. This in turn reduces the temperature of the house and the house becomes cooler.