Lesson 7 of 8 · Energy
Experiment⭐ 30 XP⚡ Spark LabMaking a Circuit Light Up
Making a Circuit Light Up.
🎯 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
This is why airplanes can fly and why rockets reach space.
Stretch Challenge
Try this in real life this week.
This week, find one thing in your house that turns one kind of energy into another.
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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