Jostling passed along
Why Does a Metal Spoon Get Hot?
Heat travels through metal because jostling atoms pass their movement to their neighbours, and metals do it best.
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Step 1 of 5
Heat is atoms jiggling about.
The hotter something is, the more violently its atoms vibrate around their places. Heat is that jiggling and nothing more.
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Step 2 of 5
A jiggling atom shoves its neighbours.
Atoms in a solid are locked close together, so one vibrating hard cannot help knocking into those beside it and setting them moving.
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Step 3 of 5
The jostling travels, but the atoms stay put.
No atom makes the journey along the spoon. Each stays roughly where it was and simply passes the movement to the next one along.
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Step 4 of 5
Metals have loose electrons that speed it up.
In a metal, electrons roam freely and carry energy across quickly, so metals conduct heat far faster than wood or plastic can.
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Step 5 of 5
This is why metal feels colder than wood.
At the same temperature, metal pulls heat out of your hand quickly while wood barely does, so the metal feels cold when it is not.
Copper conducts heat roughly 400 times better than wood, which is why pans are copper-bottomed and handles are not.
The short version
Heat moves through a solid as vibrating atoms shove their neighbours, and metals do it fastest because their loose electrons carry energy too.
Try it yourself
Stand a metal spoon and a wooden one in the same hot drink. Only the metal one becomes too hot to hold.
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