1. Take a balloon. Blow air into it. As we fill it up, it expands and it becomes harder to press the walls of the balloon. The inside air exerts pressure on the walls of the balloon.
2. Open the mouth of the balloon slightly. Air from the balloon comes out.
3. We can open the mouth less or more and control the flow of air.
4. The air in the balloon is at high pressure and it goes towards low pressure area.
5. We already know that when air moves, it is called wind. Air moves from the region where the air pressure is high to the region where the pressure is low.
