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Name: lilac
Status: student
Age: 13
Location: N/A
Country: N/A
Date: 2000

Why does metal expand?

Dear Lilac,

Metal usually expands when heated because the atoms of the metal start to move faster when they have more energy. It's sort of like handing a piece of chocolate to a 5 year old; after they eat the chocolate, he or she starts running around and bouncing off the walls, right? The chocolate gives him/her more energy, so he/she moves around more and explores more space. Same with the metal atoms; when you heat the metal you give energy to the atoms and they move around more as a result.

best wishes,
prof. topper

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