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HDTeach
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Homework Statement
Imagine I have a 3.5 kg brick at 80 °C that I put in 10l of water at 20 °C. What will the final temperature of the water be?
SHC brick = 840 J kg-1 °C -1
Homework Equations
E = mc∆θ
The Attempt at a Solution
First I calculated the energy available from the brick to heat the water:
E = mc∆θ = 3.5*840*(80-20) = 176400J
Then I attempted to calculate the temperature change:
E = mc∆θ(for brick)+mc∆θ (for water)
176400 = 3.5*840*(80-∆θ) + 10*4200*(∆θ-20)
176400 = 2940(80-∆θ) + 42000(∆θ-20)
176400 – (2940*80) – (42000*-20) = (2940*-∆θ) + (42000*∆θ)
622440 = 39060*∆θ
∆θ = 16 degrees C
I am not sure this is correct though...any ideas? Have I over-complicated this?