1. Electricity Electrical Power & Energy

2. Electrical Energy Every major appliance sold in Canada has either an “Energy Star” or “EnerGuide” label. Shows the energy consumption of an appliance over a year in kilowatt hours (kWh). By considering this information, consumers can save lots of money in a year and be environmentally conscious at the same time.

4. Electrical Power From the work and energy unit, power was defined as the amount of energy transformed in a time interval: From an electrical perspective, power is given by: Power is often measured in megawatts (1 MW = 1,000,000 W) Where: P = Power (Watts or W) V = Voltage (V) I = Current (A)

5. Example #1 How much current does a 480 W blender draw if the outlet it is connected to is 120 V?

6. The Cost of Electrical Energy Given by: cost = rate x energy transformed cost = rate x power x time OR cost

7. Example #2 What is the cost to operate each device below. Assume the rate is $0.025 / kWh. a)A 75-W stereo is operated for 16h b)An air conditioner rated at 6.5 x 10 2 W is operated for 8.2 h

8. Homework P.356 #1-6