(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A current of 10A is maintained for 1s in a resistor of 25Ω while the temperature of the resistor is kept constant at 27°C. This resistor is thermally insulated with a mass of 10g. If it has a specific heat of 836 J/kg*K. What is the entropy change of the resistor? Universe?

2. Relevant equations

3. The attempt at a solution

Ok so if the wire is thermally insulated at a constant temperature of 27°C, Q=0 therefore

W=0 because it is isothermal and adiabatic

So if entropy is

TdS= dU - dW

so ΔS = 0J/K?

However this is wrong...the answer is 5.78J/K and im confused at to how they got this... any suggestions?

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# Homework Help: Entropy involving current and resistance question

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