# Quite URGENT: Temp change equation needed when u add cold water to hot waterWatch

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#1
Quite URGENT: Temp change equation needed when u add cold water to hot water

Ya I know Thermal conductivity of water, volume of the cold water and hot water, density, specific heat capacity

so any equations to link all those so that I get a equation that will generate the decrease in temp?
0
14 years ago
#2
here ya go :
energy change = constant x no. of molecules x temp change
E = knt
0
#3
the problem is i don't know what is energy change
0
14 years ago
#4
energy is conserved (if there is no heat loss to the environment)

I get T3 = [d1V1cT1 + d2V2cT2]/[d1V1c + d2V2c]

1 = cold water, 2 = hot water, 3 = after mixing

and d=density, V = volume, c = spec. heat. capac. and T = temp.

thermal conductivity doesnt come into it, because at both times the temperature is in equilibrium
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