Characteristics of Series & Parallel Circuits

I= (as R increases; I decreases) Series Circuit: One path from the source & back If 1 device burns out, the circuit breaks & everything shuts off. The current is the same through out the circuit. IT= I1=I2 The more loads you add in series, the lower the current becomes I= (as R increases; I decreases) V R

Series Circuit: VT= V1+V2 RT= R1+R2 The potential difference is divided up among all parts of the circuit. VT= V1+V2 The resistance is added together RT= R1+R2 Examples: Christmas tree lights (the frustrating old incandescent type!)

Parallel Circuit: IT= I1+I2 More than one path from the source and back. If one device goes out, the rest are unaffected. Current is the sum of the currents from all paths. IT= I1+I2 The potential difference is the same across the source and all loads. VT=V1=V2 You can add more loads in parallel without affecting the operation of the others.

Parallel Circuit: Resistances are not added together because the electrons can go down separate paths. = + Examples: The plugs in your home. Why did the lights go out? Because they liked each other. 1 RT 1 R1 1 R2

KIRKOFF'S LAWS SERIES PARALLEL Current: Constant Current: Additive Same at all points & through the source Current: Additive current through each branch adds to total current through source. Potential Difference: Add potential diff. across all loads add up potential diff. across source. Potential Difference: Const potential diff. across each load equals each other and potential diff. source. Equivalent Resistance: + equivalent resistance of loads in series found by adding up the resistance of the individual loads Equivalent Resistance equivalent resistance of loads in parallel is lower than the resistance of any of the individual loads. It is calculated as:

Characteristics of Series & Parallel Cells

Batteries Connected in Series Doubles the voltage Maintaining the same capacity rating (amp hours). Batteries Connected in Parallel Doubling the capacity (amp hours) of the battery Maintaining the voltage of the individual batteries.