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punk_rawk_jazz
Oct8-04, 06:27 PM
Does anyone know why I end up with the wrong answer?
The question is: Determine the temperature change: 10 kg of water loses 232 kJ or heat

I went delta q is equal to m c delta t, the derived the equation delta t is equal to delta q divded by mc. I therefore did the math as 232 kJ divided by (10 kg times 4.2 x 10 ^3 j/kg C) and got 9.7 x 10 ^4, when the answer was supposed to be 5.5. Does any one know what I did wrong??


Thank you in advance

Diane_
Oct8-04, 06:38 PM
Well, I did it using your numbers and ended up with 5.5. I have two thoughts:

1) Watch your units. You're dealing with kilojoules in the numerator and joules in the denominator.

2) Watch your arithmetic: That's 232000 divided by 10 divided again by 4200.