Models, Systems & Scientific Explanations — Practice · Grade 6 Science
Chapter: Inquiry, Measurement & ModelsWhat this practice covers
By the end of Models, Systems & Scientific Explanations you should be able to:
- I can explain why a useful model is always a simplification.
- I can state the limit of a model and give an observation that falls outside it.
- I can explain what makes scientists replace one model with another.
8 questions, written answer and multiple choice, each with a worked explanation.
Vocabulary used: model, system boundary, evidence, system boundary, uncertainty.
Problem 1
Answer and explanation
It highlights arrangement and motion at a scale we cannot directly see, provided its symbols and limits are explained.
Compare the scientific meaning and reasoning after an independent attempt. A different accurate supported response can be correct; human review is required.
Problem 2
Answer and explanation
Keeping matter within a boundary is different from preventing energy transfer across it.
Compare the scientific meaning and reasoning after an independent attempt. A different accurate supported response can be correct; human review is required.
Problem 3
Answer and explanation
The surroundings and diminishing temperature difference matter; a trend over a short interval need not continue below room temperature.
Compare the scientific meaning and reasoning after an independent attempt. A different accurate supported response can be correct; human review is required.
Problem 4
Answer and explanation
No. It limits numerical population predictions, while the represented feeding relationships may still be supported.
Compare the scientific meaning and reasoning after an independent attempt. A different accurate supported response can be correct; human review is required.
Problem 5
Answer and explanation
The record is consistent with water remaining inside the sealed system while energy transfers to cooler surroundings. The 10 °C drop is not ten joules; calculating energy would require additional information. Constant measured mass does not mean every particle is motionless or that the container blocks energy.
Compare the scientific meaning and reasoning after an independent attempt. A different accurate supported response can be correct; human review is required.
Problem 6
Answer and explanation
No. Its size and distance may be deliberately exaggerated to show illumination. State whether the model is about viewing geometry or numerical scale before using it.
Compare the scientific meaning and reasoning after an independent attempt. A different accurate supported response can be correct; human review is required.
Problem 7
- model: A representation used to explain or predict selected features and relationships.
- A useful model must reproduce every feature at full size.
- A sealed system cannot exchange energy.
- One illustrative result establishes every real condition and needs no further evidence.
Answer and explanation
model: A representation used to explain or predict selected features and relationships.
A representation used to explain or predict selected features and relationships. The record is consistent with water remaining inside the sealed system while energy transfers to cooler surroundings. The 10 °C drop is not ten joules; calculating energy would require additional information. Constant measured mass does not mean every particle is motionless or that the container blocks energy.
Problem 8
- A useful model must reproduce every feature at full size.
- system boundary: The chosen limit separating a system from its surroundings.
- A sealed system cannot exchange energy.
- One illustrative result establishes every real condition and needs no further evidence.
Answer and explanation
system boundary: The chosen limit separating a system from its surroundings.
The chosen limit separating a system from its surroundings. The record is consistent with water remaining inside the sealed system while energy transfers to cooler surroundings. The 10 °C drop is not ten joules; calculating energy would require additional information. Constant measured mass does not mean every particle is motionless or that the container blocks energy.