Current Electricity Notes

Notes on Pg. 544-552

• Electric current involves electrons repelling one another and passing through a conductor
• The flow of charge is called electric current
• One ampere is one coulomb of charge moving through a point in a conductor every second
• Current is a flow of negatively charged electrons repelling one another, so current moves from negative to positive
• An ammeter is a device that measures the current
• In direct current, the current flows in a single direction from the power supply
• In alternating current, the current flow reverses often
• The path of a circuit is called a current
• Potential difference between two points in a circuit can be measured using a voltmeter
• The electrical potential energy for each coulomb of charge in a circuit is called the electric potential difference

Formulas

Electric Current

Name                                                  Symbol                                            SI Unit

Current                                                      I                                                  A (amperes)

Quantity of Charge                                     Q                                                C (coulombs)

Time                                                          t                                                  s (seconds)
1 A=1 C/1 second
It is the rate of electric charge flow over a period of time. 

Electric Potential Difference

Name                                                Symbol                                             SI Unit

Electric Potential Difference                     V                                                   V (volts)

Electric Potential Energy                      W or E                                              J (joules)

Quantity of Charge                                  Q                                                  C (coulombs)
1 V=1 J/1 C