Veda · OUT OF PURE CURIOSITY
How can we keep heat longer?
Compare how two identical cups cool
The temperature difference decreases
Both cups start at 80 °C in air at 20 °C. A larger temperature difference causes faster energy transfer in this model. Insulation increases cooling time, but the final temperature is still the surroundings’ temperature.
T(t) = 20 + 60 × exp(−t / τ)
For adults · discuss together
This simplified cooling model uses a constant air temperature. Water is well mixed and evaporation is not modelled separately. Time is accelerated; this is not a real cup measurement.
Before experience
Ask: “What do you think will happen?” Let the child check his guess first.
After the experience
What has changed? What remains the same? Where can you notice a similar phenomenon?
