Solving Thermal Physics Problem: Specific Heat Calculation

AI Thread Summary
The discussion revolves around calculating the specific heat of a metal substance given the heat required to raise its temperature. The initial calculation of 2.65 J/kg°C was incorrect due to a unit oversight, as the correct specific heat should be 2.65 kJ/kg°C. Additionally, the user seeks guidance on calculating the heat of fusion from a graph divided into segments, questioning whether to sum the values obtained for each segment. Clarification on the method for calculating and combining these values is requested. The conversation highlights the challenges faced when tackling thermal physics problems without prior classroom coverage.
metalmagik
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Sounds like Chemistry to me. So our teacher sends us all home with packets full of info on things we've never covered in class and I've got to do this. Here's one problem that I'm not sure if I did right.

What is the specific heat of a metal substance if 135 kJ of heat is needed to raise 5.1 kg of the metal from 20 deg. C to 30 deg. C?

The formula is "heat needed to raise temp" = (mass)(specific heat)(delta temp)

so I made it 135 = (5.1)(x)(10)

and I got 2.65 J/Kgdeg.C for specific heat. Is this correct? Thank you
 
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metalmagik said:
Sounds like Chemistry to me. So our teacher sends us all home with packets full of info on things we've never covered in class and I've got to do this. Here's one problem that I'm not sure if I did right.

What is the specific heat of a metal substance if 135 kJ of heat is needed to raise 5.1 kg of the metal from 20 deg. C to 30 deg. C?

The formula is "heat needed to raise temp" = (mass)(specific heat)(delta temp)

so I made it 135 = (5.1)(x)(10)

and I got 2.65 J/Kgdeg.C for specific heat. Is this correct? Thank you
Almost correct. You overlooked one small thing. You need 135 kJ of heat. You either have 2,650 J/(kg C) or 2.65 kJ/(kg C).
 
AH much appreciated thank you, if you or anyone else could answer another small question in this same topic i would appreciate it, I have a graph here separated into 5 different parts (A-B, B-C, C-D, D-E, E-F) It is a curve going upwards...I just need to know how to calculate the heat of fusion of the substance using the curve in the graph...I can use the formula and calculate the heat of fusion for each little piece but...do I add them after that? I'm just not really sure...any help is once again appreciated, if you need me to clarify or draw the graph I will, gladly. Thank you.
 
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