Science of yo-yos continued

_Elsa_

‘In a perfect world, a yo-yo could rise and fall on its string forever. But as the string spins on the plastic axle, friction (the rubbing force between two things that are in contact and moving past one another) uses up some of its energy. Although you can't see it happening, the spinning yo-yo wheels also rub against the air that surrounds them. This air resistance also eats away at the yo-yo's energy supply. If you don't keep giving the yo-yo more energy, by pumping the string up and down, it slows down very quickly and grinds to a halt. Every time you tug the string, you jerk the yo-yo so it keeps on spinning. In effect, you are recharging its energy batteries with each tug.’

‘Why does a spinning yo-yo feel weird in your hand?

Things that are moving like to carry on moving. We call this phenomenon momentum (loosely speaking, momentum means "mass in motion"; things have momentum because they have both mass and velocity). A truck speeding down the freeway has more momentum than a car going the same speed because it has more mass. A person has more momentum when they ride a bicycle than when they walk because a bicycle goes faster (it has a higher velocity or speed).’ (Source)

Let’s continue - Types of energy

Start at the beginning – Let’s learn how to use a yo-yo