Newton's Law of Cooling
Place an object at a chosen starting temperature into an ambient environment — watch it cool (or warm) exponentially toward the ambient temperature, and see the time constant control how fast it gets there.
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What you can adjust
- Starting temperature
- -20 – 150 °C
- Ambient temperature
- -20 – 50 °C
- Cooling constant (k)
- 0.05 – 1 /s
The object's temperature at t=0. Set it below the ambient temperature to see the object warm up instead of cool down.
The surrounding temperature the object eventually settles at.
How fast the object equilibrates — larger k means a shorter time constant (1/k) and faster approach to ambient.
About this simulation
What it shows
An object at a starting temperature sits in surroundings at another temperature, and its temperature is drawn over time as it settles towards the surroundings.
The key idea
The bigger the temperature difference, the faster the heat flows, so the difference shrinks exponentially: T = T_env + (T₀ − T_env)e^(−kt). The time constant is 1/k, and it warms up instead if it starts colder.
Try this
Set Cooling constant (k) to 0.15 instead of 0.3: the object takes twice as long to approach the ambient temperature, because the time constant 1/k doubles.