Please forward this error screen to 199. For the term used when referring to touchscreens, see resistive touchscreen. The electrical resistance of electromagnetic compatibility handbook kaiser pdf electrical conductor is a measure of the difficulty to pass an electric current through that conductor.
Electrical resistance shares some conceptual parallels with the notion of mechanical friction. An object of uniform cross section has a resistance proportional to its resistivity and length and inversely proportional to its cross-sectional area. All materials show some resistance, except for superconductors, which have a resistance of zero. This proportionality is called Ohm’s law, and materials that satisfy it are called ohmic materials.
In other cases, such as a transformer, diode or battery, V and I are not directly proportional. The hydraulic analogy compares electric current flowing through circuits to water flowing through pipes. Conductance is proportional to how much flow occurs for a given pressure, and resistance is proportional to how much pressure is required to achieve a given flow.