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Punnett Squares

Cross traits between two parents and watch dominant/recessive inheritance ratios emerge in this interactive Punnett Square.

Morse Code

Encode and decode messages with Morse code. Watch a signal lamp flash and hear the classic telegraph tones as dots and dashes transmit your message.

Strong and Weak Nuclear Forces

Visualize the forces inside atomic nuclei: the strong force binds protons and neutrons together, while the weak force causes radioactive beta decay.

Fusion vs Fission

Compare nuclear fusion and fission side-by-side. Watch hydrogen nuclei combine in fusion while uranium splits apart in fission—both releasing energy.

Infinite Chocolate Paradox

Watch the famous infinite chocolate illusion animate step-by-step, then reveal where the missing area actually hides.

Euler's Identity

Watch e^(iπ) + 1 = 0 come alive as a point travels around the unit circle in the complex plane, revealing how five fundamental constants connect.

Golden Spiral

Watch the golden spiral emerge as Fibonacci squares stack in a mesmerizing pattern, revealing nature's most elegant ratio.

Riemann Sums

Visualize how rectangles under a curve approximate the area beneath it. Watch the approximation improve as you add more rectangles.

Parabola Focus

Watch parallel rays reflect off a parabolic mirror and converge at the focus point—the principle behind satellite dishes and telescopes.

Derivative Visualization

Drag a point along a curve and watch the tangent line show the slope (derivative) at each point.

Monte Carlo Pi

Estimate pi using random points. Watch as the ratio of points inside a circle to total points converges to reveal the value of pi.

Conic Sections

Tilt a plane through a cone to reveal circles, ellipses, parabolas, and hyperbolas—the four conic sections.

Exterior Angle Sum

Walk around any polygon and watch the exterior angles always sum to 360 degrees. Drag vertices to reshape and see the math in action.

Triangle Angle Sum

Drag the corners of a triangle and watch as the three interior angles animate together to form a straight line, proving they always sum to 180 degrees.

Voronoi Diagrams

Tap to place points and watch space divide - like a city where each hospital serves the closest residents. Each pixel is colored by the point nearest to it.

Pi from Polygons

Watch a polygon inscribed in a circle approach pi as you add more sides. An interactive demonstration of Archimedes' method.

Ellipse Foci

Drag a point around an ellipse and watch the sum of distances to both foci stay constant—the defining property of an ellipse.

Bézier Curves

Drag control points to shape smooth curves and see how digital design tools create perfect curves.

Sine Wave Tracer

Watch how circular motion creates sine waves. A rotating point casts its shadow, tracing out the wave in real-time.

Thales' Theorem

Explore Thales' Theorem: any point on a semicircle forms a right angle (90°) with the diameter endpoints. Drag the point to see it stay constant.

Inscribed Angle Theorem

Drag a point around an arc and watch the inscribed angle stay constant. Discover why all inscribed angles subtending the same arc are equal.

2-Stroke Engine

See how a 2-stroke engine completes intake, compression, power, and exhaust in just one crankshaft revolution.

Displacement & Volume

Drop objects into water and watch the level rise. Discover how Archimedes measured volume through displacement.

Binary

Convert numbers between decimal and binary. Tap bits to toggle them ON/OFF and see how powers of 2 combine to form any number.

Wind Tunnel

Place different objects in a virtual wind tunnel and watch how air flows around them. Compare drag coefficients of a cow, truck, sports car, and more.

Airplane Lift

Watch thousands of air particles flow around a wing. See how angle of attack creates lift through pressure differences, and what happens during a stall.

Radio Signals

Explore how radio waves transmit information through amplitude (AM) and frequency (FM) modulation.

Coin Flip Probability

Flip coins and watch randomness converge to 50/50 — the Law of Large Numbers in action.

Orbit and Speed

Discover why satellites closer to Earth move faster. Adjust orbital altitude and watch how speed changes.

Rockets

Launch rockets with adjustable thrust and fuel. Watch staging in action and see why dropping empty tanks is the key insight that makes space travel possible.

Lifecycle of a Star

Watch a star evolve from nebula to its final fate. Adjust mass to see how it determines whether a star becomes a white dwarf, neutron star, or black hole.

Supernova

Watch a massive star collapse and explode. The heavy elements forged in this explosion—like iron and gold—seed the cosmos.

Aurora Borealis

See how solar wind particles funnel along Earth's magnetic field lines to create the Northern Lights at the poles.

Galaxy Collision

Watch two spiral galaxies collide and merge over hundreds of millions of years. Stars swirl into tidal tails before settling into a single elliptical galaxy.

Black Hole Lensing

Watch light bend around a black hole, distorting the stars behind it while a glowing accretion disk warps dramatically due to extreme gravity.

Lightning

Watch electrical charge build in storm clouds and discharge as branching bolts. Tap anywhere to call down lightning.

Reaction-Diffusion

Watch organic Turing patterns emerge as two chemicals react and diffuse. These same equations explain zebra stripes, leopard spots, and seashell patterns.

Flocking

Watch birds form mesmerizing murmuration patterns using three simple rules: stay close, align direction, and avoid collisions.

Fireworks

Launch fireworks on different planets. See how gravity affects how high they soar and how fast particles fall.

Cellular Automata

Explore emergence: how complex behavior arises from simple rules. Cells live or die based on their neighbors, creating self-organizing patterns like gliders and oscillators.

Strange Attractors

Watch particles trace the mesmerizing Lorenz attractor — a beautiful demonstration of chaos theory where tiny differences lead to wildly different paths.

Levers

Balance a see-saw by dragging kids of different weights. Discover how distance from the fulcrum trades off with force.

Pulleys

Discover how pulleys create mechanical advantage. Drag the rope to lift a heavy weight with less force - but more rope to pull!

Refraction

See how light bends when passing from air into water, glass, or diamond. Drag the light source to change the angle.

Coriolis Effect

See how Earth's rotation makes moving objects appear to curve. Tap to launch balls and watch their paths deflect differently in each hemisphere.

Retrograde Motion

Watch Mars appear to move backward against the stars as Earth overtakes it on its faster inner orbit.

Pythagorean Theorem

Drag the triangle corners to explore how a² + b² always equals c² in a right triangle.

Greenhouse Effect

See how CO2 traps heat in Earth's atmosphere. Adjust CO2 levels and watch temperature rise as infrared radiation gets absorbed and re-emitted.

Food Web

Remove a species from the ecosystem and watch the cascading effects ripple through the food web.

Gears

See how connected gears trade speed for torque. A smaller output gear spins faster but lifts less weight, while a larger output gear spins slower but lifts more.

Friction

Compare how different surfaces affect stopping distance. Push blocks across ice, wood, rubber, and sandpaper to see friction in action.

Jet Engine

See how a jet engine works: air is compressed, fuel burns, and hot gas shoots out to create thrust.

Fractal Explorer

Zoom into the infinite complexity of the Mandelbrot and Julia sets. Discover how simple math creates endlessly intricate patterns.

Simple Harmonic Motion

See how a spring, pendulum, and circular motion all produce the same sine wave pattern — revealing the mathematical unity behind oscillations.

Water Cycle

Drag the sun to control temperature and watch water evaporate, form clouds, and fall as rain in this interactive water cycle simulation.

Vector Addition

Drag vectors to see how they add tip-to-tail. Explore perpendicular, opposite, and parallel cases.

Fourier Series

Build any waveform by stacking sine waves. See how square, triangle, and sawtooth waves are made from simple harmonics.

Tides

Drag the Moon around Earth to see how its gravity creates tidal bulges. Watch your location experience high and low tides as Earth rotates.

Galton Board

Drop balls through a grid of pegs and watch them form a bell curve, demonstrating how random events create a normal distribution.

Doppler Effect

Watch how an ambulance siren sounds higher as it approaches and lower as it drives away. Tap to move your listening position.

Buoyancy

Explore why objects float or sink by dragging them into water and comparing their density to water's density.

Natural Selection

Watch evolution in action with the peppered moth example. Toggle pollution to change the environment and observe how moth populations adapt over generations.

Lens and Mirrors

Explore how lenses and mirrors form images. Drag an object to see ray tracing in action and understand real vs virtual images.

Collisions

Launch balls of different masses and observe elastic vs inelastic collisions. See how momentum is always conserved while kinetic energy is only conserved in elastic collisions.

Predator-Prey

Watch population boom-bust cycles emerge as foxes hunt rabbits. Adjust birth and death rates to see how ecosystems find balance.

Ideal Gas Law

Explore how pressure, volume, and temperature relate in a gas. Adjust the piston and temperature to watch particle behavior change.

Magnetic Fields

Place bar magnets and current-carrying wires to visualize magnetic field lines using compass needles that align in real-time.

4-Stroke Engine

Watch the inner workings of a piston engine through its four-stroke cycle: intake, compression, power, and exhaust.

Seasons

Discover why we have seasons by exploring Earth's axial tilt and orbit around the Sun. See how sunlight angle changes throughout the year.

Electric Field Lines

Place positive and negative charges to see the invisible force field between them. Drag to move, double-tap to remove.

Unit Circle

Explore the unit circle by dragging a point around it and watch sine, cosine, and tangent values update in real-time.

Wave Interference

Explore how waves from two sources combine to create interference patterns with bright constructive and dark destructive regions.

Projectile Motion

Launch projectiles at different angles and velocities to explore how gravity affects their trajectory, range, and flight time.

Pendulum

Explore how length and gravity affect a pendulum's swing. Drag the bob, adjust parameters, and see the period formula in action.

Lunar Cycle

Explore moon phases, eclipses, and the lunar node precession cycle in this interactive 3D simulation.