Imagine yourself running the vacuum cleaner over the carpet when all of sudden—a sock. Boom. It’s stuck in the hose, the whine of the vacuum getting higher andhigher, louder andlouder. It sounds like overload is imminent, like the motor is working way too hard. But is it? To know, let’s look at some cool physics principles. Vacuum cleaners don’t actually suck. They blow. No, really. They use a fan that blows air out of a hole.