8.02 Lecture Notes - Lecture 1: Electromotive Force, Resistor, Internal Resistance
Document Summary
After the second light bulb is connect, the current from the battery compared to when only one bulb was connected is higher. Battery ( ), resistor (r), capacitor (c), inductor (l), switch (s) The work per unit change around a closed path is called electromotive force emf. This is a bad name because it is not a force. Let f denote the force per unit charge, then the emf is. If a conducting closed path is represented, then. Inside battery: non-zero chemical force f inside battery (zero outside), moves charges through a region in which static electric eld e opposes motion. Ideal battery: net force on charges is zero. Extend path through external circuit where f is zero. Assign current and current direction in each branch. Circulation direction across each element de nes before and after side of element. De ne electric potential difference across a circuit element by v = v(after) - v(before) = v(a) - v(b)
