Teacher Demonstration
Use the live model as a shared screen demonstration before students try their own predictions and observations.
Physics / Modern Physics
Three State Decay Theory
Explore Three State Decay Theory as an interactive EJS simulation for modern physics.
1. Watch or Launch
Launch the Interactive
Open the simulation, adjust the controls, and compare what changes on screen before answering the concept-check questions.
2. Big Ideas
Key idea Measurement is a bridge between the physical world and a model. Good measurements require appropriate instruments, units, precision, uncertainty, and evidence-based reporting.
What Students Can Learn
- Choose a suitable measuring instrument.
- Read scales systematically.
- Use units and sensible significant figures.
- Discuss uncertainty and repeated readings.
Guiding Question
What is being measured, how is it read, and how reliable is the result?
3. Try the Investigation
Identify the Quantity
Decide whether the model is about length, time, mass, vector quantity, or data.
Use the Instrument or Display
Read the scale, graph, or numerical display carefully.
Record With Units
State the measurement with suitable unit and precision.
Evaluate Reliability
Discuss uncertainty, repeat readings, or possible errors.
4. Teacher Notes
Lesson Use
Use this resource to strengthen measurement habits: read carefully, record with units, and explain reliability.
Discussion Prompts
Ask: What instrument or display gives the evidence? What is the smallest meaningful reading? What could cause error?
Teaching Moves
Ask students to give the reading and a short uncertainty comment. This makes measurement more than just writing a number.
5. Concept Check
These questions are generated from the topic and the concept illustrated by the simulation. Use them after students have explored the model.
Concept Score
Correct first attempts build a streak and unlock higher point multipliers on this device.
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0current streak
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Answer each question once to build your streak.
1. What should come with a measured value?
2. Why choose a suitable instrument?
3. What does uncertainty remind us?
4. Why repeat a measurement?
5. What is a good measurement explanation?
7. Learning Pulse
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