Agenda Bell Work• Notes: Electric Power• Calculations • What is the difference between a series and a parallel circuit?• Household Energy Use – • When more devises (light Gizmo bulbs) are added to each, what happens to:• HW: Chp 12 pg 192-195, – Voltage 204 – Currant – resistance• Test Friday
1. Explain how moving electrons can do work2. Calculate Power given two variables
Moving charges can do work – heat a circuit or turn a motor Power is the rate of using energy
Electrical energy may be transformed to: Mechanical energy (a motor) Light (a lamp) Thermal energy (a heater) or other forms
Power = current x voltage Units Watts = amperes x volts What power is needed to operate a clock radio if it draws a current of 0.05 amps from your household circuit?
Electrical Energy is supplied to our houses by generators and motors This energy is purchased from power company’s The electrical energy travels through power lines to individual homes to be sold to the homeowner
The units of energy sold is represented in units of 1000 watts delivered for one hour, or units called kilowatt-hours. 1 kilowatt = 1000 watts 1 kilowatt-hour = 1000 watts delivered for 1 hour The more electrical power a consumer demands, the more kilowatts are used