Sunday, February 7, 2010

A bath tub full of lukewarm water hold more heat than a teakettle full of boiling water? True or False?

Let, mass of the tub water is m1.dT1 is the change in temperature due to boiling of the water from a reference temperature. Cp is the specific heat of the water, then for the first case, Q1=m1*cp*dT1


similarly, if mass of the kettle water is m2. dT2 is the change in temperature due to boiling of the water from a reference temperature, then Q2=m2*Cp*dT2. So, above question will be true if m1*dT1%26gt;m2*dT2, other wise false.A bath tub full of lukewarm water hold more heat than a teakettle full of boiling water? True or False?
i think it is trueA bath tub full of lukewarm water hold more heat than a teakettle full of boiling water? True or False?
True, I agree with coffeebr....
I would figure it out this way;


Say a bath tub is 22x52x9 = 10296 cubic inches or 169 liters.


Say my teakettle holds just one liter.


Boiling teakettle 100 deg C times 1000 ml = 100,000 calories


Lukewarm bath tub at say 32 deg C (=90F) is:


32 times 169,000 ml = 5,408,000 latent heat calories.


Answer: TRUE


NOTE; you have to be a little more picky with units to be exactly correct, but the logic is the same. Just note that Specific heat is really measured in cal/g. 1 cal/gr = 4.184 J/kg = 1.80 Btu/lb
false
True. Unless the teakettle is really really big and the tub is really small.

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