# electric current & circuits. what is the difference between static electricity and current...

Post on 01-Jan-2016

223 views

Category:

## Documents

Embed Size (px)

TRANSCRIPT

• Electric Current & Circuits

• What is the difference between static electricity and current electricity?Static electricity is stationary or collects on the surface of an object, whereas current electricity is flowing very rapidly through a conductor.The flow of electricity in current electricity has electrical pressure or voltage. Electric charges flow from an area of high voltage to an area of low voltage.Water pressure and voltage behave in similar ways.

• Electric CurrentLots of negative charge (high PE)Lots of positive charge (low PE)Electrons flow from high PE (negative terminal) to low PE (positive terminal)

• Voltage (V) Difference in PE causes pressure VoltageA voltmeter is used to measure the voltage of a component in a circuit

• Voltage = Electrical Pressure You may hear voltage also be referred to as a potential differenceDam and water example

• Current (I)The flow of electrons Current

• The pressure of the water flowing through the pipes on the last slide compare to the voltage (electric potential) flowing through the wires of the circuit. The unit used to measure voltage is volts (V).The flow of charges in a circuit is called current. Current (I) is measured in Amperes (A).Current is measured with a tool called an Ammeter

• Resistance (R)The opposition to the flow of an electric current, causing the electrical energy to be converted to thermal energy or light.

• Factors that affect wire resistance Temperature

LengthThickness

• The Sink ModelVoltage the pressure of that particular sinkMore pressure = more flowCabin shower vs. home shower Current the actual flow of waterResistance the handle of the sinkLess resistance = more flowMore resistance = less flow

• CircuitLight bulbs not lit, because there is no longer a complete circuitCircuit: A complete path for electrons to flow

• SymbolsWire

Switch (open)

Battery

Light bulb

• SymbolsResistors

Ammeter

Voltmeter

• Series CircuitsOnly one path for the electrons to flow through

• Series CircuitChrismas Vacation

• Parallel CircuitsMore than one path for the electrons to follow

• Parallel Circuits

• Power SourceAlternating Current vs. Direct Current

AC DCAC When the direction of electron movement regularly changes

DC Electrons move continuously from the negative terminal to the positive terminal

***

Recommended