I was reading about ohmic and non-ohmicresistors, but I'm unsure as to what thedifference between them is. I understand that ohmic devices have a constantresistance, meaning the voltage-current graph produced for it will show a straight line and that non-ohmic devices have a changing resistance, leading to a curved voltage-current graph. What I don't understand is why this happens. Non-ohmic resistors have changingresistance because as the voltage increases, the electrons transfer more energy to the atoms of the conductor, meaning there are greater vibrations leading to an increase in the temperature and resistance. But why is this not the case with ohmic devices? Is there not any increase in the vibrations of atoms in ohmic devices? Everywhere I've read, I've found that ohmic devices have a "limited temperature range", but that doesn't make sense to me. Surely any increase in voltage will lead to an increase in temperature, so a limit on the temperature is not possible. Thanks in advance.