Answer to Check the Recipe, Herb!

 
     This stew's not cooking fast enough! We need to raise the temperature of the water another 10° Celsius. 

     Let's see...20 kg of water and 70 kg of person, both with a specific heat capacity of 4.2 Joules/(gram-Celsius degree) would take...??? 

     Help me Herb! How many Joules of heat energy will I need? By the way, the tub, being made out of special physics materials, does not have to be considered in the calculation. 

The quantity (Q) of energy involved in a temperature change equals the product of specific heat capacity, mass, and change in temperature. So,

Q = (4.2 J/gC°)(90x103g)(10C°)
    = 3.78 x 106 J = 3.78 MJ

 
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