“A hot object has greater average kinetic energy but may not have greater total kinetic energy “
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Imagine the number balls in a lottery machine. They’re bouncing around in the machine like crazy. They’re knocking into each other and into the sides of the container they’re in. This is like the atoms in a hot object (specifically, this is most similar to a container of hot gas).
Now, turn the same machine off so that the balls aren’t getting bounced around anymore and drop it out of a third story window. Now the balls aren’t bouncing into each other as much anymore. Instead, they’re all going the same direction – down.
All those number balls bouncing against each other are cancelling each other’s energy out. Taken individually, each one is very energetic, but taken as a group, they’re not going anywhere or doing anything useful. The number balls falling out of the window aren’t individually very energetic since they’re not bouncing around anymore, but taken together they might damage a car parked on the street.
At the atomic level, heat is kinetic energy, but at the macro (object) level, almost all of that kinetic energy cancels out and you’re left with a hot object that’s sitting still. A cold object moving quickly may have more kinetic energy than a hot object sitting still.
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