Learn
First Law of Thermodynamics
The simulation above lets you drag Q (heat in) and W (work out) sliders and watch how internal energy, temperature, piston position, and molecule behavior all respond — enforcing ΔU = Q − W in real time. The preset buttons demonstrate three classic thermodynamic processes.
Try this simulation yourself
Drag the Q slider to add or remove heat — watch the flames light up and molecules speed up
Drag the W slider to make the gas do work — watch the piston rise as the gas expands
Keep an eye on the ΔU card — it always equals Q minus W, no matter what you do
Tap the presets to see real thermodynamic processes in action:
Isobaric — heating at constant pressure, gas expands and does work
Adiabatic — no heat, pure compression raises temperature
Isochoric — heating in a sealed container, all energy stays inside
Try setting Q and W to opposite extremes — can you make ΔU equal zero?