Specific Heat & Heat Capacity

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MedPR

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What's the difference between heat capacity and specific heat? A higher value for either means that the object won't get as hot (requires more energy to heat).
 
I always thought they were pretty much the same thing with very little difference. But taken from the words of one person on yahoo:

" specific heat capacity is the heat energy that is required to change the temperature of a unit quantity of a substance by a certain temperature interval.

The heat capacity of a substance is a measure of how well the substance stores heat. Whenever we supply heat to a material, it will necessarily cause an increase in the material's temperature. The heat capacity is defined as the amount of heat required per unit increase in temperature."

I dont think theres a big difference.
 
I always thought they were pretty much the same thing with very little difference. But taken from the words of one person on yahoo:

" specific heat capacity is the heat energy that is required to change the temperature of a unit quantity of a substance by a certain temperature interval.

The heat capacity of a substance is a measure of how well the substance stores heat. Whenever we supply heat to a material, it will necessarily cause an increase in the material's temperature. The heat capacity is defined as the amount of heat required per unit increase in temperature."

I dont think theres a big difference.

So there is technically a difference in terms of what you are really talking about, but qualitatively they have the same effect. Sounds good to me 🙂 Thank you.
 
Specific heat capacity is:

Energy needed per unit mass per degree celcius raised
J / (g x *C)

Heat Capacity is not per unit mass anymore, it is amount of energy needed per degree celcius raised FOR an object of KNOWN mass. In other words it is the specific heat multiplied by the mass of the object of interest.

J/ *C

Its analogous to density and specific density in a sense. to get the density of an object you multiply the specific density by the density of water. To get the heat capacity of an object you multiply the specific heat by the mass of the object.
 
Specific heat capacity is:

Energy needed per unit mass per degree celcius raised
J / (g x *C)

Heat Capacity is not per unit mass anymore, it is amount of energy needed per degree celcius raised FOR an object of KNOWN mass. In other words it is the specific heat multiplied by the mass of the object of interest.

J/ *C

Its analogous to density and specific density in a sense. to get the density of an object you multiply the specific density by the density of water. To get the heat capacity of an object you multiply the specific heat by the mass of the object.

So in q=mcdeltaT, the c is "specific heat capacity"

But in q=cdeltaT, the c is "heat capacity"

So it's the same thing, just in a different form?
 
So in q=mcdeltaT, the c is "specific heat capacity"

But in q=cdeltaT, the c is "heat capacity"

So it's the same thing, just in a different form?

Yes. It's the same thing but one is for a specific amount of matter the other is in general. The closest analogy is density vs mass.
 
Yes. It's the same thing but one is for a specific amount of matter the other is in general. The closest analogy is density vs mass.

Do you guys think they'll give you the units on the real thing? If not, it seems like it could be a pretty tricky calculation problem. They give you the mass of an object, but also give you the heat capacity then tell you to find q. If you don't know the units, or don't know that heat capacity already takes mass into account, you'll probably get it wrong.
 
Do you guys think they'll give you the units on the real thing? If not, it seems like it could be a pretty tricky calculation problem. They give you the mass of an object, but also give you the heat capacity then tell you to find q. If you don't know the units, or don't know that heat capacity already takes mass into account, you'll probably get it wrong.

That feels like a slightly sleazy trick. But no idea what's fair game at the real test. I'll bet a beer that you won't have such a question but that's not a very high stake.
 
That feels like a slightly sleazy trick. But no idea what's fair game at the real test. I'll bet a beer that you won't have such a question but that's not a very high stake.

Well I've found that units are actually pretty helpful for ruling out answers, so maybe they'll throw some hint in there. In my mind there will always be 1-3 questions on there just to prevent people from getting everything right.
 
Well I've found that units are actually pretty helpful for ruling out answers, so maybe they'll throw some hint in there. In my mind there will always be 1-3 questions on there just to prevent people from getting everything right.

That's more likely to be one of the thermal-kinetic-mechanical BS that we were discussing. Anyway, you'll know a lot better in two days.


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