ELECTRICAL CIRCUITS All you need to be an inventor is a good imagination and a pile of junk. -Thomas Edison
What is it?
The movement of electrons through a conductive material Electrons bump into other electrons in adjacent shells (called valence shells) and continue down the path What is it?
Electrons will only flow if there is a complete circuit for them to flow around Electrons, which are negatively charged, emerge from the negative terminal of the power supply Conventional notation, however, is to refer to the electricity as emitting from the positive terminal of the power supply
VOLTAGE RESISTANCE CURRENT How you should be thinking about electric circuits: Voltage the “speed”, and subsequent force, that pushes the current through the circuit Water analogy The higher the water fall the more “voltage”
VOLTAGE RESISTANCE CURRENT How you should be thinking about electric circuits: Resistance friction that impedes flow of current through the circuit Water analogy rocks in the river
VOLTAGE RESISTANCE CURRENT How you should be thinking about electric circuits: Current The actual “substance” that is flowing through the wires of the circuit (electrons!) Water analogy The water molecules
Understanding Electricity Air is conductive…if you have enough voltage to push the electrons through it (i.e. – lightening) 10,000 volts might not hut you…but if it pushes just 1 amp of current through your heart it can be fatal If the circuit has no resistance, it’s called a short circuit and infinite current will flow until the circuit fails (i.e. – melts or depletes)
V = I x R Ohm’s Law I = Current (Amperes) (amps) V = Voltage (Volts) R = Resistance (ohms) Georg Simon Ohm (1787-1854)
V = I x R Ohm’s Law So more voltage will provide you more current And more resistance will provide you less current Georg Simon Ohm (1787-1854)
Simple Circuits Parallel circuit Series circuit Many paths for electricity 1 light goes out and the others stay on Series circuit All in a row 1 path for electricity 1 light goes out and the circuit is broken