Lesson 4 of 5 · Simple Electricity
Experiment⭐ 30 XP⚡ Spark LabMaking a Circuit Light Up
Simple Electricity.
🎯 Your mission
Predict it first. Then prove yourself right (or wrong).
⚡ The twist
The opposite of what you expect is often what happens.
Mind = Blown
🔥 A bolt of lightning is 5 times hotter than the surface of the sun.
Make a hypothesis first
Predict: what happens if you double the force?
What You'll Learn
A bulb lights only when there is a complete loop from one end of the cell, through the bulb, and back to the other end. Break the loop anywhere — a gap, a switch, a loose wire — and everything stops, not just the part after the break.
Key Words
Tap a word to see its definition.
Materials Needed
- cell
- bulb and holder
- connecting leads
- switch
Safety First
- Use a single cell or low-voltage supply only — never mains electricity.
- Disconnect the cell between changes so nothing overheats.
Steps
Read the explanation above and note the two key terms before you start.
Build a circuit with a cell, wires and a bulb, then break it in three different places one at a time. Record what happens each time and draw the circuit with the standard symbols.
Record what actually happened, including anything that did not match what you expected.
Write a conclusion that answers the question this lesson opened with, and state your uncertainty.
Check Your Understanding
Question 1
1 of 2A bulb lights only when the circuit is:
Where you see this in real life
You use this every time you flip a light switch, ride a bike, or kick a ball.
Stretch Challenge
Try this in real life this week.
Time how long a small ball rolls down something, then change the slope and try again.
For the dinner table
“Show me something at home that uses this kind of energy.”
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Making a Circuit Light Up
Predict it first. Then prove yourself right (or wrong).
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