Year 8 Science · Unit 4 · Lesson 15
Apply Worksheet
Learning Goals
Pick the best model
For each question a scientist wants to answer, state which type of model would work best (physical, conceptual or mathematical) and give one reason.
| The scientist wants to... | Best type of model | One reason why |
|---|---|---|
| Show young students the shape and chambers of the heart. | ||
| Calculate how far a car travels in 3 seconds at a steady speed. | ||
| Show how water moves between the sea, sky and land. | ||
| Predict how many fish will be in a bay next year. |
Strengths and limitations
Scenario
A teacher shows the class a globe as a model of the Earth. The globe shows the shape of the planet and the position of the continents and oceans, but the mountains are painted flat and the cities are not shown at their real size.
(a) What type of model is the globe? Give one reason for your answer.
(b) State one strength of the globe as a model of the Earth.
(c) State one limitation of the globe and explain why that limitation matters for a scientist studying mountains.
1. Engineers test a scale model of a bridge in a wind tunnel before building the real one. Explain one reason this is useful.
2. The particle model shows atoms as tiny solid balls, even though atoms are not really like that. Explain why scientists still find this model useful.
Wrap Up
In one sentence, why is it important to know a model's limitations before you trust its results?