Cold butter on hot toast doesn’t stay cold for very long. Some of the heat from the toast passes into the butter, and so the butter becomes warm, too. The heat is a form of energy. Heat energy can spread. Heat energy always flows from something warmer to something cooler. The movement of molecules passes the heat along.
A slice of toast is a solid piece of bread. But the molecules in the bread move. They wriggle and jiggle, even though they are held together. As the bread is toasted, the heat from the toaster makes the molecules speed up.
Cold butter is solid, too. But its molecules are moving very slowly. When you spread the cold butter onto the hot toast, some of the fast-moving toast molecules bump into the slow-moving butter molecules. That makes the butter molecules move faster. The jiggling motion moves from molecule to molecule until the butter is soft and warm.
Put five coins with different dates in a small box. Show them to some friends and explain that you will read your friends’ minds. While your back is turned, get your friends to choose one of the coins and remember its date. Ask each friend to hold the coin tightly in one hand for a moment and to concentrate on the date. When everyone has had a turn, ask the last person to drop the coin in the box. Turn around right away and touch each coin lightly. Four of the coins will be cool – but the fifth will be warm, because it has taken heat energy from your friends’ hands. Pick that coin, read the date, and amaze your friends!
Picture Credit : Google