Here is the question:Inside all vacuum cleaners is a high speed fan. Explain how this fan causes dirt to be picked up by the vaccum cleaner.I am a tutor but dont understnad this so just give em the answers and ill choose your answer, for the kids.
the fan causes the vacuum cleaner to suck-in the air. as the moving air passes by the dirt particles, it's the INTERACTION of the moving air and the dirt that causes the dirt to be drawn along with the air. basically, the air molecules bash into the dirt particle and impart energy (momentum) to the dirt, and this is what makes it move. if there was no air motion over the dirt, then the dirt particles would not respond to the vacuum cleaner.
