Electric Props
Circuits require:

Complete path
	* Power source
	* Direct current (DC): batteries
	* Alternating Current (AC): gernators, power grid
	* Load
	* Lamps

Switch (to open the path)

Basic Circuits

* Direct Current circuit (flashlight)
Current flows from Source (battery) to Switch to Load (lamp) to other terminal of Source.

* Alternating Current (table lamp)
Current flows from Source (power company) to Switch (dimmer) to Load (lamp) to other terminal of Source.


There are two types of basic circuits: Series and Parellel

	* Series current: flows through each device in turn.

	* Parallel: has multiple paths from Source terminal to terminal.


A Little Basic Electricity

Electricity: is moving electrons

Basic units:

Resistance (R): opposition to current flow, Measured in Ohms
	Low resistance= conductors
	High Reistance= insulators

Electromotive Force or EMF (E): Provides the "push", Measured in Volts

Current (I): amount of electricity, Measured in Amps

Purpose is to perform Work
The work done is measured in Watts

Basic relationship expressed by two formulas:

Ohm's Law:

R=E/I  or  R=V/A

Power Formula:

W=VA

Watts equals Volts multiplied by the Amps


Typical load: Flashlight bulbs:

	PR4:	2.33 V	.27 A	.63 W
	PR2:	2.38 V	.50 A	1.19 W
	PR12:	5.98 V	.50 A	2.98 W


Typical flashlight batteries are rated at 1.5 v.

Solution: you can put voltage sources in Series and Parellel also!

Two 1.5 v batteries in Series = sum of the individual voltages.

Two 1.5 v batteries in Parallel = same voltage and sum of the amperage.

6 v lamps in Parallel with a large 6 v. battery for longer life.

An array:
	* 3 strings of 4 small batteries wired in series (to 
increase voltage) 

	* then the strings wired in parallel (to increase amperage, to 
feed a load of three 6 v. lamps in parallel

results in a higher capacity 6 v. circuit.