# Heat capacity?You bring a 650 g wrench into the house from your car. The house is 21 C warmer than the car, and it takes 2.48 of energy to warm the wrench by this amount. Find the heat capacity of...

Heat capacity?

You bring a 650 g wrench into the house from your car. The house is 21 C warmer than the car, and it takes 2.48 of energy to warm the wrench by this amount. Find the heat capacity of the wrench.

bandmanjoe | Middle School Teacher | (Level 2) Senior Educator

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Heat capacity is a specified amount of energy per kilogram of mass needed to raise the temperature by one degree Celsius.  I am assuming the 2.48 is Joules of energy, so if we take the formula for heat capacity, which is C = energy/mass, we could insert the 2.48 on top and the 650 grams of mass on the bottom.  We would need to convert the mass to kilograms, as heat capacity is expressed in Joules per kilogram.  To do this, divide 650 by 1000, and you get .65 kilograms of mass.  So now the math problem would look like this:

C= 2.48 J/.65 kg

C= 3.82 J/kg

So the heat capacity of the wrench is 3.82 Joules per kilogram.  That is the amount of energy needed to raise the temperature of that substance by one degree Celsius.  Heat capacity knowledge can be quite a useful piece of information, predicting substances that might not be able to bear heat absorption and still function well.

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