Lesson 4 of 8 · Lab Skills
Experiment⭐ 30 XPUncertainty and Significant Figures
Lab Skills.
🎯 Your mission
Set it up. Test it. Be amazed.
⚡ The twist
Nature loves to surprise the careful watcher.
Mind = Blown
🔬 The more you look, the more nature shows you.
Make a hypothesis first
Before you start: write down what you think will happen, and why.
What You'll Learn
Every measurement carries an uncertainty, usually half the smallest scale division or the spread of repeats. A calculated answer can never be more precise than its least precise input, so quote results to the same number of significant figures as your weakest measurement.
Key Words
Tap a word to see its definition.
Materials Needed
- ruler with millimetre divisions
- book
- calculator
Safety First
- Have an adult check your set-up before you start, and tidy everything away afterwards.
Steps
Read the explanation above and note the two key terms before you start.
Measure a book's three dimensions with a ruler, record the uncertainty on each, and calculate the volume. Express the answer to a justified number of significant figures and state the percentage uncertainty.
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 ruler with 1 mm divisions gives a typical uncertainty of about:
Where you see this in real life
This shows up in your everyday life more than you'd think.
Stretch Challenge
Try this in real life this week.
Try one experiment in real life this week — even a tiny one.
For the dinner table
“What's the most surprising thing you learned today?”
Next Smart Experiment
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Share this experiment
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Uncertainty and Significant Figures
Set it up. Test it. Be amazed.
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