electrical current
DESCRIPTION
Electrical Current. I. What is Electrical Current?. Definition The rate at which charges pass a given point Units of measurement Amperes Shortened to Amps 2 Types of Current DC AKA: direct current Electrons always flow in the same direction. - PowerPoint PPT PresentationTRANSCRIPT
Definition The rate at which charges pass a given point
Units of measurement Amperes Shortened to Amps
2 Types of Current DC▪ AKA: direct current▪ Electrons always flow in the same direction.▪ Batteries in a camera or a flashlight use DC
AC▪ AKA: alternating current▪ The electrons can move in either direction▪ Electrical outlets in your home use this.
Definition The measure of how much work is needed to
move a charge between 2 points. Units of measurement
Volts (V) Relationship between voltage and current
As long as there is voltage between 2 points on a wire, charges will flow in the wire.
The greater the voltage:▪ The greater the current.
Different batteries have different voltages Car batteries need a bigger current to start the
car so they have a higher voltage.
1.5 Volts
9 Volts
6 Volts
Definition The opposition to the flow of electric charge Like “electrical friction”
Units of Measurement Ohm’s Represented by the Greek letter omega ( )
Variables which affect resistance Material ▪ Good conductors have a:▪ Low resistance▪ Like Copper
▪ Insulators have a:▪ High resistance
Temperature▪ As you increase a metals temperature▪ You increase resistance
▪ Superconductors▪ Metals at very low temperature who’s resistance is virtually 0
Definition: These change chemical or radiant energy into
electrical energy Parts
Electrolytes▪ Mixture of chemicals which allow charges to flow
Electrodes▪ Made of conductors▪ Points at which charges enter and leave the cell.
2 Types Dry Cell▪ Electrolytes are solid or paste▪ Normal batteries
Wet Cell▪ Electrolytes are liquid▪ Car batteries
Ohm’s Law Relates current, voltage, and resistance Voltage = Current X Resistance V = I X R
Electrical Power Power = Voltage X Current P = V X I Measured in Watts