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Thermal equilibrium

  • Thread starter TT0
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TT0
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Homework Statement


A hot (800 K) iron nail of mass 150 g is placed into a 1.0 kg of water at 25°C. What is the common temperature of the 2 objects once they have reached thermal equilibrium? Assume no change of state of the water.

Heat capacity of iron nail is 450 J/kg/K
Heat capacity of water is 4138 J/kg/K

Homework Equations


Q=mc∆T

The Attempt at a Solution


Q lost in nail=Q gained in water

let T = final temperature

0.15*450*(800-T)=1*4138*(T+25+273)
T=-280.38 K

I don't know why it is negative. Can someone explain what I did wrong?
 

Answers and Replies

  • #2
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(T+25+273) should be a difference between the final temperature and initial temp.
 
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  • #3
TT0
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I see thanks!
 
  • #4
TT0
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Is the answer 33.06 C?
 
  • #5
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Seems reasonable
 
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  • #6
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Thanks again!
 

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