Lesson 5 of 10 · Energy
Experiment⭐ 30 XP⚡ Spark LabPower: How Fast Energy Is Transferred
Power: How Fast Energy Is Transferred.
🎯 Your mission
Predict it first. Then prove yourself right (or wrong).
⚡ The twist
Energy never disappears — it just hides somewhere else.
Mind = Blown
⚡ Static electricity is the same physics as lightning, just smaller.
Make a hypothesis first
Before you start: which will move faster, and why?
What You'll Learn
Power is energy transferred per second, in watts. A 2,000 W kettle transfers twice as much energy per second as a 1,000 W one, so it boils the same water in half the time and costs the same to do it.
Key Words
Tap a word to see its definition.
Materials Needed
- kettle
- thermometer
- measuring jug
- stopwatch
Safety First
- Hot water scalds — have an adult pour, and never overfill the kettle.
- Keep the kettle and its flex well away from the sink.
Steps
Read the explanation above and note the two key terms before you start.
Time how long a kettle takes to raise a measured mass of water by a measured temperature rise. Calculate the energy needed and divide by the time to estimate the kettle's power, then compare with its rating plate.
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 device transfers 6,000 J in 3 s. Its power 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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Power: How Fast Energy Is Transferred
Predict it first. Then prove yourself right (or wrong).
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