Inquiry, Measurement & Models — Chapter review · Science 6: Matter, Energy & Earth Systems, Grade 6
What makes a scientific explanation traceable and testable? Under one defined mass-and-draining method, which equal-sized towel sample retains more water?
Review the key ideas
Scientific Inquiry: Questions, Evidence & Explanations
Science answers one narrow kind of question: the kind where you can collect evidence that would change your mind. The question is not whether an idea sounds sensible but whether there is a measurement that could show it is wrong.
Variables, Controls & Repeated Trials
A fair test changes one thing and holds everything else steady, and compares the result against a group you deliberately did nothing to. Without that second group you cannot tell whether your change caused the difference or whether it would have happened anyway.
Metric Measurement, Units & Uncertainty
Every measurement is a number plus a unit plus an honest statement of how far off it might be. Leaving out any of the three turns a measurement into a claim nobody can check, and in at least one famous case it destroyed a spacecraft.
Tables, Graphs & Patterns in Data
A table records what you measured; a graph shows what it does. Choosing the wrong graph, or drawing the axes carelessly, can hide a real pattern or invent one that was never in the numbers.
Models, Systems & Scientific Explanations
A model is a deliberate simplification that is kept because it predicts things correctly, and every one of them is wrong in some way on purpose. Knowing where a model stops working is as much a part of understanding it as knowing what it explains.
Problem 1
Answer and explanation
The sunny tray lost 4 g more in the hour, but sunlight and surface area both differ. Greater exposed area could also affect evaporation. Use identical trays with equal water amounts and matched timing, varying only the intended exposure. The present evidence describes a difference without isolating its cause.
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
No. It shows water at that moment; washing, irrigation, or another source could be involved. A cause needs additional information.
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
Width and length both change. Length can affect bending, so the larger load does not isolate width. Keep length, material, support spacing, and counter placement the same, vary width, and use several fresh strips for each treatment. Compare all recorded loads under the same failure rule.
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. Counter count is not comparable when counter mass differs. Use identical counters or measure load mass, then repeat the corrected method.
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 lengths are 6.5 cm and 6.4 cm, or 65 mm and 64 mm. The 1 mm difference is observed reading variation; the values do not establish a length exact to many decimal places. Check alignment and use the ruler’s scale consistently.
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
1.2 kg = 1,200 g. A gram is smaller than a kilogram, so the numerical count grows when the same mass is expressed in grams.
Compare the scientific meaning and reasoning after an independent attempt. A different accurate supported response can be correct; human review is required.
Problem 7
Answer and explanation
The unwrapped cup decreases by 9 °C and the wrapped cup by 5 °C. The wrapped cup cools less over ten minutes under the stated comparison. This supports slower cooling if volumes, lids, location, and measurement are matched; it does not prove the wrapping prevents all energy transfer.
Compare the scientific meaning and reasoning after an independent attempt. A different accurate supported response can be correct; human review is required.
Problem 8
Answer and explanation
Check the labeled axis and full difference: 2 units. A shortened axis can emphasize that difference, so the graph should make its scale explicit rather than suggest a huge proportional change.
Compare the scientific meaning and reasoning after an independent attempt. A different accurate supported response can be correct; human review is required.
Problem 9
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 10
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.