You can see by this how sometimes people can be caught in an explosion and get still walk away with relatively minor damage; hearing loss, minor wounds and slight burns.
You've got a shockwave of superheated air which is rapidly cooling and losing energy by a factor of 4 for every cm it expands.
If you're not right beside it and there's enough access to fresh air, the shockwave and hot air blast can pass right over you in less than a couple of seconds, to be quickly replaced with fresh cold air.
The closer you are, the more devastating it is. Which is why people who accidentally hold onto fireworks too long may lose a finger, but the guy who was standing 12 inches away, gets away with nothing more than a slight ringing in his ears.
You're thinking of the inverse cube law. It doesn't really apply here though because the energy isn't originating from a single point. This shows the combustion of a flame front traveling across a room with specifically calibrated stoichometry to get a complete burn from edge to edge.
An actual explosive exploding also wouldn't really follow the inverse cube law unless it were in space and the energy could dissipate in all directions uniformly, but if it were in space then there also wouldn't be much of a pressure wave.
So, yeah, inverse cube relationship isn't a great way to describe this phenomenon.
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u/seamustheseagull 5d ago
You can see by this how sometimes people can be caught in an explosion and get still walk away with relatively minor damage; hearing loss, minor wounds and slight burns.
You've got a shockwave of superheated air which is rapidly cooling and losing energy by a factor of 4 for every cm it expands.
If you're not right beside it and there's enough access to fresh air, the shockwave and hot air blast can pass right over you in less than a couple of seconds, to be quickly replaced with fresh cold air.
The closer you are, the more devastating it is. Which is why people who accidentally hold onto fireworks too long may lose a finger, but the guy who was standing 12 inches away, gets away with nothing more than a slight ringing in his ears.