Specific Heat (The Very Concept)

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aleph_0
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So I don't get the concept of specific heat. I'm doing an ODE problem and I've never even looked at science, not even in high school. The book defines the specific heat of a substance as: The ratio of the quantity of heat required to raise the temperature of a unit of substance by one degree, to the quantity of heat required to raise the same unit of water by one degree.

Now take for instance a 50-lbs ball of iron heated to 200 degrees, where iron has a specific heat of .11. A priori I would have thought that the total quantity of heat would be 50(200) because, hey, temperature is like average quantity of heat in an object, right? And the object weighs 50-lbs, which can basically be treated like its mass. So the product should give the total heat, no? Huh? Right?

Well I would be wrong. It looks like the quantity of heat in such an object is 50(.11)(200) and I don't exactly get why. What in god's name does that ratio have to do with this sort of thing?

Thank you.
 
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hi aleph_0! welcome to pf! :smile:

it means that if you need X amount of heat to raise 50-lbs of water by 200°, then you only need 0.11 times X to raise 50-lbs of iron by 200° :wink:
 
OH MY GOD that was the perfect answer! So clear, so simple. THANK YOU!

(Part of this is general excitement about learning a concept; the other part is too much coffee.)