PHYS 11 Lecture Notes - Lecture 10: Metal Resistance, Electric Potential Energy, Electric Charge
Document Summary
Charge tries to flow to create neutrality. Electromagnetic force is one of 4 basic forces. Opposite charges are attracted to each other. Mass not relevant to the electric force. More mass does not mean more charge. Coulomb: unit of electric current (change on 6 x 10 18 electrons) Electric current i = amount of charge q flowing/time t. E. g electron flowing in wire, or ions flowing is a liquid or gas. Electrons flow in direction opposite to current. Most material presents resistance to current flow. Free electron hit ions in metal, transfer energy from electron to ions, causing ions to vibrate faster. Bulb contains a very thin wire, through which current flows. Designed to melt when heated by too much current (break, no more current) Insulators have very high resistance and impede current flow. Due to the way electrons are grouped in the substance. Wires are brittle and unstable, then large current would stop, heat up rapidly, and explode.
