Lesson 4 of 7 · Electricity
Experiment⭐ 30 XP⚡ Spark LabSeries and Parallel Circuits
Electricity.
🎯 Your mission
Run the experiment. Find out what really happens.
⚡ The twist
The opposite of what you expect is often what happens.
Mind = Blown
🎢 You feel weightless on a roller coaster because you and the seat are falling at the same speed.
Make a hypothesis first
Predict: what happens if you double the force?
What You'll Learn
In series the same current passes through every component and potential differences add. In parallel each branch has the full supply potential difference and the branch currents add. That is why household lighting is wired in parallel — one failed lamp leaves the rest lit.
Key Words
Tap a word to see its definition.
Materials Needed
- low-voltage supply
- two lamps and holders
- ammeter
- voltmeter
- leads
Safety First
- Low-voltage supply only.
- Switch off before unscrewing a lamp — the holder can be hot.
Steps
Read the explanation above and note the two key terms before you start.
Build two lamps in series and measure current at three points and voltage across each lamp. Rebuild in parallel and repeat. Then unscrew one lamp in each arrangement and record what happens to the other.
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 2In a parallel circuit, the potential difference across each branch 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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Series and Parallel Circuits
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