Solve Solid Compressability Homework Problem Involving Copper Block

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SUMMARY

The discussion centers on solving a homework problem involving a copper block with a mass of 0.25 kg, focusing on isothermal pressure changes and their effects on heat, work, and internal energy. The user has calculated the volume change due to pressure but lacks the molar mass of copper to determine the number of moles required for further calculations. The user proposes that since the temperature remains constant, the change in internal energy is zero, leading to the conclusion that heat equals negative work. The correct formula for work in an isothermal process is identified as W = PΔV.

PREREQUISITES
  • Understanding of thermodynamic principles, specifically isothermal processes
  • Familiarity with the concept of compressibility in materials
  • Knowledge of the ideal gas law and its application in thermodynamics
  • Basic calculations involving work done in thermodynamic systems
NEXT STEPS
  • Research the molar mass of copper for accurate calculations
  • Study the derivation and application of the ideal gas law in isothermal processes
  • Learn about the relationship between heat, work, and internal energy in thermodynamics
  • Explore examples of compressibility effects in different materials under varying pressure and temperature
USEFUL FOR

Students studying thermodynamics, particularly those tackling problems related to isothermal processes and material properties, as well as educators seeking to enhance their teaching materials on these topics.

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Homework Statement



Hello, I have a problem involving a copper block of mass .25kg. They have a given compressibility due to pressure change, and compressibility due to temperature change. They give the density for copper as well. They tell you that the pressure changes from P1 --> P2 isothermally.

It then asks what the amount of heat leaving the system is
The work done on the copper block
and the total change in internal energy


Homework Equations






The Attempt at a Solution



what I've done already is figured out the volume change due to the pressure change.

Using this volume change I can theoretically find the work done using -nRT*ln(Vf/Vi). The only problem is I don't have a value for the moles. I could find it if i had the molar mass of copper, but I don't, and this is a practice exam problem.

If i assume that because temperature change is 0, the change in internal energy is 0. Then heat will equal negative work. but i have a strong feeling this is wrong.
 
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In an isothermal process, the work done is simply the pressure times the change in volume, i.e.
<br /> W = P\Delta V<br />
Does that help?
 

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