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You know how you somehow end up getting smoke in your eyes wherever you stand around a bonfire? Well, it turns out that’s not a curse! It’s much more easily explained with physics.

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Imagine: You're having a good time around a fire when out of nowhere the smoke blows straight into your face. Naturally, you just get up, you move to get out of the way. You go back to having a good time again and the smoke is suddenly blowing right back in your face! It was over there when I was over there no I'm over here it's over here. You and the people near you, you move out of the way, everything's fine for a bit until, once again, your eyes start to sting. Eventually, everyone gets huddled it seems like has been smoke-free but you know what happens next, your friends say that you are cursed because you brought the smoke with you as you moved. There is no curse which is honestly too bad because curses can be broken. the laws of physics cannot. So all that smoke starts with fire and fires release a lot of energy as heat, and air molecules nearby absorb some of that heat and start to move faster. Since temperature is just an average measurement of how much energy molecules have, that means the air starts heating up too. Those speedy molecules collide with their slower neighbours and send those neighbours in the opposite directions, freeing up space for the hot air near the fire to expand. This whole chain of events results in the air near the fire becoming less dense than the air around it. Now, you may have heard that less dense air rises, and that is true. It's usually better to live on the top floor in the winter and in the basement in the summer. You also may have heard that less dense air rises because it weighs less than the air it replaces, which is also true, but it's more of a definition than an explanation. It just means that less dense air rises because it's less dense. the reason dense stuff sinks is because as you get further above the ground there is less and less air above you. So air down at the ground has to push with a lot of force to support the weight of all the air above it. and it's not just air everything down here at the ground pushes against the weight of the air above it now if you were light enough that the force of gravity on your body pulled you down less than the air pushed you up, you would be lifted off like a hot air balloon.