Welcome to the Science Explain Virtual Lab — a set of interactive simulations built from scratch with code. Every diagram on these pages is drawn live in your browser, so you can change the numbers and watch physics, chemistry and biology respond in real time.
There is nothing to install and nothing to sign up for. Pick an experiment below, drag the sliders, and see what happens.
MechanicsProjectile MotionChange speed, angle and gravity, then watch the pathMechanicsCollisions and MomentumChange masses, velocities and restitutionOpticsReflection and RefractionSnell's law and total internal reflectionAcousticsBeats and Standing WavesInterference you can see and hearElectricityOhm's Law CircuitVoltage, current and resistance in one loopBiologyMitosisWatch one cell divide into two identical cellsChemistryAcid–Base Titration CurveAdd base drop by drop and watch the pH jumpChemistryMolecular ShapesRotate real 3D geometries: water, methane, benzene and moreOpticsConvex Lens ImagingMove the object and trace the rays to find the imageThermodynamicsIdeal Gas LawChange n, T and V and watch the pressure respondMechanicsSimple PendulumTest whether the period formula really holdsAcousticsDoppler EffectSee the wavefronts bunch up and hear the pitch changeMechanicsInclined Plane and FrictionFind the angle where a block starts to slideOpticsPrism DispersionWhy white light splits into a spectrumOpticsDouble-Slit InterferenceLight behaving as a wave, fringe by fringeElectricityRC Charging CircuitWatch a capacitor fill and empty over timeBiologyDNA ReplicationUnzip the double helix and build the copyBiologyEnzyme ActivityHow temperature and pH change reaction rateBiologyFood Web and Energy FlowRemove one species and watch the web respondChemistryChemical EquilibriumDisturb a system and watch Le Chatelier's principle workChemistryReaction Rate and Activation EnergyThe energy barrier that decides how fast things happenChemistryElectrolysis and Faraday’s LawPlate metal with electricity and predict the massChemistryPeriodic TrendsMap radius, ionisation energy and electronegativityChemistryAtomic OrbitalsExplore s, p and d electron clouds and their nodesChemistryLimiting ReagentWhich reactant runs out first, and how much product you get
How to use the labs
- Drag the sliders to change the starting conditions. The drawing and the numbers update immediately.
- Watch the readouts under each simulation — they show the actual calculated values, not decorations.
- Use the buttons to replay, reset, or jump to an interesting case.
- On a phone the simulations still work; the controls stack vertically and the canvas resizes to fit your screen.
Why we build these with code
Most science sites illustrate an idea with a static picture. A static picture can only ever show one set of conditions. Drawing the same idea with code means you can ask “what if?” — what if gravity were weaker, what if the resistance were ten times larger, what if the light hit the boundary at a steeper angle? That question is where real understanding starts.
Every visual here is generated in your browser at the moment you load the page, which also means every image on these pages is original.