Does heating an electromagnet cause change in its magnetic field? Does heating an electromagnet cause change in its magnetic field as well and vice versa?
 A: I'll assume 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:
$$
R = R(T_0)\left[1 + \alpha\left(T - T_0\right)\right]
$$
You can google to 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 $\alpha = 0$, nothing happens.


There is a table on wikipedia which contains resistivity of several materials and their temperature coeficient arround $T_0 = 293K$.
