chunks of fluid carry energy from one part to another People make use of convection when they go hot air ballooning. Hot air rises because it expands when heated and therefore becomes less dense. The hot air is then captured by the balloon. The volume of the balloon is chosen so that the buoyancy force on it is larger than the weight of the balloon and the weights attached to it (that includes people), so the balloon rises. The rising hot air eventually cools, which means now it is more dense and can start falling again. But it can't go straight down since there is rising hot air below it. Therefore, it shifts sideways then starts to fall. Air circulating in this way is called a convection current. Convection currents on a global scale
chunks of fluid carry energy from one part to another People make use of convection when they go hot air ballooning. Hot air rises because it expands when heated and therefore becomes less dense. The hot air is then captured by the balloon. The volume of the balloon is chosen so that the buoyancy force on it is larger than the weight of the balloon and the weights attached to it (that includes people), so the balloon rises. The rising hot air eventually cools, which means now it is more dense and can start falling again. But it can't go straight down since there is rising hot air below it. Therefore, it shifts sideways then starts to fall. Air circulating in this way is called a convection current. Convection currents on a global scale