MENTOR TEACHING · THERMAL ENERGY | Classroom copy · 1 October 2026

Meet every requirement

100 g, start 10°C, room 22°C, 20 min. Final ≤15°C in EVERY trial; ≤5 tokens; ≤18 mm added thickness. Covered liquid water; cups/lids, mass, starting temperature, duration, exposure and reading procedure match within and across trials. Surroundings stay at the stated room temperature. No ice, phase change, active heating/cooling, direct sunlight or meaningful evaporative cooling. Each trial uses fresh samples. Accuracy is not supplied.

Supplied design record

Constructed teaching data: these values were invented for this activity, not collected in an experiment.

DesignTokensAdded mmTrial 1 final °CTrial 2 final °CTrial 3 final °C
P7141313.513
Q521141414.5
R418141614
S51814.51514.5

Fictional response: “P wins because all its temperatures are lowest. R also works because its average is below 15°C.”

1.Evaluate both statements. Check temperatures, budget and thickness separately for every row. Which supplied design meets the whole brief?

2.Write or say a bounded recommendation that includes its weakest displayed temperature margin and a useful next test. Explain why numerical margin is not a reliability guarantee.

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MENTOR TEACHING · THERMAL ENERGY | Classroom copy · 1 October 2026

Fresh recheck · What if none qualifies?

100 g, start 10°C, room 22°C, 20 min. Final ≤15°C in EVERY trial; ≤4 tokens; ≤18 mm added thickness. Covered liquid water; cups/lids, mass, starting temperature, duration, exposure and reading procedure match within and across trials. Surroundings stay at the stated room temperature. No ice, phase change, active heating/cooling, direct sunlight or meaningful evaporative cooling. Each trial uses fresh samples. Accuracy is not supplied.

Supplied design record

Constructed teaching data: these values were invented for this activity, not collected in an experiment.

DesignTokensAdded mmTrial 1 final °CTrial 2 final °CTrial 3 final °C
U514151515
V4191414.514
W416141614

1.Is there a feasible design? Check each failed requirement. Recommend an honest next step without inventing a successful design or changing the rules silently.

Do not choose a winner merely because the question contains design data. “None meets the brief” can be the supported conclusion.

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