|
|
 |
Stretching and bendingImagine taking a football or a soccer ball and squashing it. That takes effort and we call this energy. When the ball is squashed it has more energy than when it has its normal shape.Balloons are just the same except that they take much less effort to squash. This means they have less energy. Balloons are made out of elsatic like elastic bands. They are both stretchy. The effort it takes to stretch them is called stretching energy. Surfaces can also have another type of energy called bending energy. This just like the effort it takes to bend a bamboo stick. It is a principle of science that things like to have the smallest energy possible. For a balloon this means that they tend to be round. This makes the stretching energy smallest. For the human red blood cell the bending energy is more important and makes the shape different.
|
|
