Hello everyone, From what i know electrical resistance for metals is a constant, but in fact it varies with temperature but not voltage. Explanation for metals and temperature is something like "heat, which is in fact average speed of electrons, does obstruct tranmission of other electrons called also electrical current, thus higher temperature = higher electrical resistance" But I am not aware that voltage would affect resistance of metals (are there any extreme limits?). Now the hard part. How can you explain the fact that high voltage does actualy decrease volume resistance of insulation materials? I am not saying there is any suitable analogy to previous example, but I am realy begging for solid explanation of this phenomenon. I would prefer explanation on microscopic scale. But any enlightement will be appreciated! PS: I believe this could be better explained by material engineers, than electrical engineers.