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An introduction to voltage theory

Task 1

View the prezi below


Then take the energy quiz


Task 2

Click on this link and click on "Run Now"

Drag components to the screen to make the circuit below:


  • Right click on the bulb on the left
  • Select “change resistance”
  • Adjust the resistance to around 3.5 ohms (does not need to be exact)


  • Using the same method, change the resistance of the middle bulb to 20 ohms and the bulb on the right to 10 ohms
  • Right click on the battery
  • Change the voltage to about 25 volts

Look at the circuit. Which bulb is giving out the most energy per second? Which is giving out the least? How can you tell?

Drag the ammeter to different wires in the circuit. What do you notice?

Connect the voltmeter in parallel with each of the bulbs. Record the voltages. What is the relationship between the energy given out per second and the voltage measured?

Connect the voltmeter in parallel with the battery and record the voltage. What do you notice about this voltage and the voltages across the bulbs? Why is this?

Add a blog post with your findings and explanations and post a link to it in the comments section below - don't forget to check out what others have written and give feedback!

Task Discussion