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Thermal Detective

FOLLOW THE TEMPERATURE TRAIL

Follow the heat. Question the timeline.

A warm object holds a clue about its past. See how different assumptions change the time you can infer.

RECONSTRUCT A POSSIBLE PASTEDUCATIONAL MODEL
Scroll the graph sideways to explore the full curve ↔

The shaded interval shows possible elapsed times under your assumptions. Lines show the earliest and latest cooling histories.

FOLLOW YOUR CURIOSITY

Try a little experiment.

Predict. Change. Compare.

Choose an experiment, predict the result, then explore.

THE SCIENCE BEHIND THE PLAY

Work backwards

Newton’s cooling model links the current temperature to the starting temperature, surroundings and cooling rate. Working backwards requires assumptions about all three.

A range tells the story

The highlighted interval spans the earliest and latest times allowed by your input bounds. It is an assumption-based interval, not a statistical confidence interval.

Forensic connection

Postmortem cooling is called algor mortis. Bodies have internal temperature gradients, variable insulation and changing surroundings. Real investigations combine multiple lines of evidence; this warm-object exercise cannot determine a real time of death.

A model, with boundaries.

A fictional warm-object teaching model, not a forensic estimator. Assumes a single uniform temperature, constant surroundings and constant positive k. Measurement error is omitted. No early cooling plateau, metabolism, evaporation or changing environmental history. Parameter bounds are independent assumptions, not calibrated probabilities.

THERMAL DETECTIVE

Changelog

v2.0.0 · November 1, 2026

v1.1.0 · November 1, 2026

v1.0.0 · November 1, 2026

UNDER THE SURFACE

A model you can question.

Equations and technical constants below use Celsius and SI units internally, independently of the display unit. Changing units preserves the experiment and saved settings.

T(t) = Ta + (T0 − Ta) exp(−kt); t = ln[(T0 − Ta)/(T − Ta)] / k. The earliest time uses the lowest starting temperature and highest k; the latest uses the highest starting temperature and lowest k.

A fictional warm-object teaching model, not a forensic estimator. Assumes a single uniform temperature, constant surroundings and constant positive k. Measurement error is omitted. No early cooling plateau, metabolism, evaporation or changing environmental history. Parameter bounds are independent assumptions, not calibrated probabilities.

Sources & related explorations

Original PopFun code and illustrations. Background sources support the physical principles; they do not validate the chosen teaching parameters. Playback takes about 24 seconds to traverse the displayed time span. All labs start paused. Save/load keeps settings, not playback position. CSV contains model data and the settings that produced it.