After watching this video, we have noticed that we are using forces all day long. We have also realised how many thing a force can do.
For instance, a force can change the shape of an object. That can be easily checked with the help of a balloon full of water:
Can you guess which force is changing its shape in the following picture?
We have also noticed that its shape also changes if we place the balloon on a table... Therefore, there must be a force acting uppon it!