So the problem Im working on is.. A 100 cm long copper wire of radius 0.45 cm has a potential difference across it sufficient to produce a current of 5.0 A at 20°C. Find a) What is the potential difference. b) If the temperature of the wire is increased to 200°C, what potential difference is now required to produce a current of 5.0 A(adsbygoogle = window.adsbygoogle || []).push({});

I solved part a easily by finding the resistance of the wire and plugging that into V=IR with the solution being 1.34mV.

Now for part b i used the equation R=R0[1+alpha(T-T00)] and plugged back into V=IR but my solution keeps coming out wrong... please help me out here im totally confused...

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# Homework Help: Temperature variation of resistance

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