Calculating Linear Expansion with Specific Heat Capacity and Mass Density?

Thread starter Kara4566
Start date Apr 19, 2019
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Expansion Linear Linear expansion

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The discussion revolves around calculating linear expansion using specific heat capacity and mass density. The initial attempt at a solution was incorrect, prompting a request for assistance. There is uncertainty regarding whether the heat capacity value of 390 J/K should be interpreted as specific heat capacity of 390 J/(kg K). Clarification on this point could help in utilizing the provided mass density effectively. Accurate interpretation of these values is crucial for solving the problem correctly.

Apr 19, 2019

Kara4566

Homework Statement: A 1.0m long rod of metal has a diameter of 0.75cm. This metal has
a coefficient of linear expansion α = 4.8 × 10−5 1/K, a density of 9.7 ×10^3 kg/m^3, and heat capacity of 390 J/K.
How much energy needs to be added as heat to increase the length of the rod by 7.5 × 10−3m?

Relevant Equations: change in Length= (Initial Length)(Coefficient of linear expansion)(change in temperature)

Above is my attempt at a solution, however, this did not yield the correct answer. Any help is greatly appreciated!

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Apr 19, 2019

TSny

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I wonder if the heat capacity of 390 J/K is really meant to be a specific heat capacity of 390 J/(kg K). Then, you can make use of the mass density given in the problem.

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