Electric Power and Energy

Electric power is the rate at which charge carriers

• pass through an area

• do work

• move through a potential difference

• collide with atoms

What does power mean?

• Joules transferred per second
• Electron flow per second
• Speed of electrons
• Electron energy

Which of the following equations is an equation for power, involving current and resistance?

• P= I/V

• P = IR

• P = IVR²

• P = I²R

Which of the following is an equation for power, involving voltage and resistance?

• P = V/R

• P = V²/R

• P = VR

• P = V²R²

A kilowatt-hour is equal to ____________ joules.

• 3,600

• 360,000

• 3,600,000

• 360,000,000

What is the unit of power?

• ohm

• volt

• ampere

• watt

What does the pie chart show?

• The amount of electricity used in an average home. 
• All of the devices that use electricity. 
• Which are the best devices for energy. 
• None of these

What group of devices uses the most electricity in the average home? 

• Lighting and Heater
• Refrigerator 
• Computer's, TV's, and other device 
• Heater and Water Heater

What is the purpose of an electric meter?

• To track the amount of electricity used. 
• To show how fast it moves. 
• To show what device is being used. 
• None of the above. 

If the hair dryer and the vacuum cleaner are both on, what is the power used?

• 2600 watt

• 400 watt

• 2200 watt

• 1100 watt