Why do balloons fly into the sky? Why do balloons fly into the sky?

1, balloons are usually filled with hydrogen or helium. Hydrogen or helium is much lighter than air with the same volume, so balloons filled with hydrogen or helium will have greater lift. If you hang a big basket under the balloon, you can take people into the sky. In addition, there is a hot air balloon filled with hot air. We know that hot air is lighter than cold air. After the balloon is filled with hot air, it will be floated by the surrounding cold air, making the balloon rise. If the heat is controlled, it can stay at different heights.

When the balloon flies to a certain height, it will explode. When the balloon rises in the air, the external air pressure changes with the increase of height. The higher the balloon flies, the thinner the air will be, the less the air density will be, and the more the gas density inside the balloon will be, so the balloon will slowly expand. When the balloon material cannot continue to expand, the balloon will explode and cannot continue to rise.