amacorrit80

2022-07-20

Does heating an electromagnet cause change in its magnetic field as well and vice versa?

Tolamaes04

your electromagnet is an inductor powered by a battery with constant potential $V$. The magnetic field is proportional to the intensity running on the wires. $B\propto I$. We know: $V=RI$, where $R$ is the resistance of the inductor. Its a very simple model as you can see...
For a small variation of temperature from initial temperature ${T}_{0}$, the resistance can be approximated with a linear relation:
$R=R\left({T}_{0}\right)\left[1+\alpha \left(T-{T}_{0}\right)\right]$
find $\alpha$ for a given material arround ${T}_{0}$ that you want to work with. So, in the vicinity of ${T}_{0}$, and with the temperature coeficient $\alpha$ measured/given, we can now conclude:
- If $\alpha >0$, resistance increases, current decreases, magnetic field decreases.
- If $\alpha <0$, resistance decreases, current increases, magnetic field increases.
- If $\alpha =0$, resistance decreases, current increases, magnetic field increases.
Temperature coeficient arround ${T}_{0}=293K$

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