Conductor allows electric current flow in one or more directions. Current flows through momentum transfer between mobile charge carriers. Metals are ideal conductors due to delocalized electron sea
Elements are divided into metals, metalloids and nonmetals based on shared properties. Metals are shiny, good conductors, form alloys and have basic oxides. Metalloids are metallic-looking, semiconductors with amphoteric oxides. Nonmetals are dull, poor conductors, form acidic oxides
Signals travel as electromagnetic waves at 50-99% of light speed in vacuum. Cables act as waveguides, guiding energy-carrying waves. Electromagnetic waves enter conductors within milliradian of surface. Copper at 60 Hz has velocity of 3.2 m/s
Metallic bonding arises from electron cloud between metal ions and conduction electrons. Electrons are delocalized in all three dimensions, forming a single molecule. Electron deficiency allows electrons to migrate and change states easily
Electric current is the flow of charged particles through conductors. Current is measured in amperes (A) and represented by symbol I. Current can be measured using ammeters or other devices
Temperature changes cause Pt100 sensor resistance to change. Constant current (1-3 mA) applied to sensor generates voltage drop. Voltage drop must be transmitted to evaluation unit with minimal loss