Interactives

Open the shared ripple tank for two-dimensional wave interference.

Shape harmonics, play notes, and inspect waveform and spectrogram views.

Probe firelight, embers, moonlight, stars, neon, and fireflies with an in-scene spectrometer.

Open the shared N-body gravity sandbox.

Explore the Earth-Moon-Sun system in 3D, advance time, and walk on Earth or the Moon.

Drag the Moon around its orbit in a top-down Sun-Earth-Moon view and watch the lit fraction and phase name change.

Fly through a Sun-centered 3D solar system, advance time, and land on solid worlds.

Open each of Kepler's three laws to see its description and a matching interactive: stretch an ellipse, sweep equal areas, and link orbital period to size.

Fire a cannon from a mountaintop and watch the path trace out, from a short parabola-like arc to a full orbit, with the view zooming out to follow.

Hop a bunny along a number line to meet vectors as one-dimensional hops that add up.

Drag a vector on a grid and read its components, magnitude, and direction.

Hop a bunny head-to-tail along two vectors in either order to see they sum to the same resultant.

Chain head-to-tail hop vectors to guide a bunny around hedges to the carrot.

Slide a scalar to stretch, shrink, and flip a vector, watching negation reverse its direction.

Steer a bunny with arrow keys or WASD, adding one unit vector per hop, to munch carrots that respawn around the field.

Slide an object against a ruler and watch the honest reading become a mark give-or-take half a division — finer marks, smaller doubt.

Combine two measurements and read the uncertainty off the bracket of plausible results, then check it against the add/multiply shortcut rules.

Measure π from round objects and test whether each error bar catches the true value — the error-bar overlap test for comparing experiment to theory.

Fit the same RC-charging data with a straight line and with an exponential, and let the residuals show which model is wrong.

Slide the time constant until the residuals stop looking random, mark both edges, then compare your range with the chi-square answer.

Click through the seven SI base units to compare their modern constant-based definitions with everyday scales.

Click metric prefixes to see their powers of ten applied across common SI units and derived units.

Move a coefficient and exponent to see how scientific notation becomes ordinary decimal notation.

Watch a pixel-art hedgehog act out the motion the kinematics graphs describe, and scrub through it a moment at a time.

Walk the shape of three target graphs in front of a Vernier motion detector and see how close you get, scored live.

Place a ball anywhere on a ramp-and-table sketch and watch it roll through two photogates and off the edge.

Time a rolling ball through two Vernier photogates, predict where it will land off the table, then test it on the floor.

Extract position and time data from your own video, then plot and fit it to measure velocity and acceleration.

Connect position, velocity, and acceleration with graph-driven one-dimensional motion.

Read average and instantaneous acceleration from a velocity graph, and the change in velocity from the shaded area under a(t).

Cut a velocity graph into constant-velocity strips and watch the sum of their signed areas close on the displacement.

Use acceleration controls to stop inside target zones.

Watch the hedgehog run a figure eight with its position, velocity, and acceleration vectors drawn on, and split the acceleration into the parts that change speed and direction.

Drag a launch vector and watch its horizontal and vertical components, v₀cosθ and v₀sinθ, change.

Aim, launch, and compare two-dimensional projectile trajectories.

Explore how acceleration vectors shape two-dimensional motion.

Place dots on a field grid to trace a cat with steady eastward velocity and a northward velocity that ramps up, then check against the answer.

Explore spring, normal, tension, gravity, friction, and net force diagrams with Newt the physics frog.

Set two opposing pushes and the mass of Newt's sled, then watch a motion map show how net force and mass set the acceleration.

Tap a link between two objects to see its third-law force pair drawn in the scene: a falling ball, Newt on a table, hanging by his tongue, or pushing a box.

Draw a boundary around objects in an interaction diagram and watch external links become a free-body diagram while internal pairs drop out.

Model three pushed blocks as chains of springs, and move a cut through the stack to see that the force there is the mass ahead times the acceleration.

Choose the forces acting on Newt in four situations, see the diagram you described, and check it against the real one.

Push Newt along a floor of adjustable roughness and watch static friction match the push until it gives way to kinetic friction.

Press a block onto a rough surface and watch the asperity tips flatten: the touching length, and with it the friction limit, grows in step with the load.

Drag a floor under a block held by atomic bonds, and read the static peak and sliding average of the total friction force.

Record a cart rolling down a ramp with a Vernier motion detector, fit a line to its velocity graph, and read off the acceleration.

Drag a ball to a height and let it fall, watching gravitational potential energy convert into kinetic energy on a stacked energy bar chart.

Build a 3D roller coaster, release the train, and read speed, g-forces, and the kinetic/potential energy ledger live.

Adjust relative motion and read events, worldlines, and light cones.

Compare a local gravitational field with an accelerating elevator scene.

Trace shortest paths on curved surfaces to build intuition for geodesics.

Drag quiet pendulums behind the text while reading about period and frequency.

Open equation plots and see how amplitude, frequency, and phase reshape motion.

Tune amplitude, mass, stiffness, and damping while tracking energy exchange.

Sweep a driving frequency and watch amplitude and phase respond inline.

Drive coupled oscillators and compare normal-mode responses.

A full-width water-wave field embedded around the introduction to wave motion.

Compare transverse and longitudinal medium motion side by side.

Adjust amplitude, wavelength, and frequency for traveling waves.

Add traveling pulses point by point to see reinforcement and cancellation.

Switch string and pipe boundaries to compare reflected waves.

Compare nodes, antinodes, strings, and air-column harmonics.

Watch live microphone input or an example sound as frequency against time, with an optional measurement overlay.

Tune light frequency and intensity in an inline photon-emission scene.

Build an interference pattern from single-particle detections.

Sample measurement hits from a localized quantum wave packet.

Compare bound-state potentials and the discrete energies they permit.

Watch a free Gaussian wave packet move and spread from momentum uncertainty.

Evolve a one-dimensional packet as it reflects, transmits, and tunnels through a barrier.

Run a split-step Schrodinger simulator with slit, barrier, and free-packet presets.

Drag a probe around a point charge to read the r̂ unit vector and the field it sets up.

Combine the fields of two point charges and find where the net field vanishes.

Place charges, choose monopole, dipole, or charged-row presets, draw field lines, and launch a test charge.

Tilt a flat surface and change its area to explore the magnitude and sign of electric flux.

Inspect individual faces of a box in a uniform field and see inward and outward flux cancel.

Move charges inside and outside 3D Gaussian surfaces and compare enclosed charge with total flux.

Roll a mass on a 1D potential energy curve for a spring or gravity, tracking the energy exchange.

Tilt a 3D landscape into a top-down map and follow contours at equal 100-meter elevation intervals.

Visualize the electric potential V(x,y) of a point charge as a color map with equipotential contours.

Combine the potential color map, equipotentials, field arrows, and a test charge for any charge configuration.

Drag the plates, change their area, slide in a dielectric, and disconnect the battery to compare fixed-V and fixed-Q behavior.

Drag to apply a field and watch conduction electrons drift through the lattice against their random thermal motion.

Play the relaxation that charges a conducting block’s faces and drives the field inside it to zero.

Throw a switch and watch surface charge spread around the loop, moving the potential drop between the switch gap and the resistor.

Drag resistors, batteries, capacitors, inductors, and switches onto a grid, wire them up, and run a transient simulation with a live scope.

Switch between the star frame and the spinning ship frame and drop a ball to feel centrifugal and Coriolis effects.

Adjust radius and angular speed while tangent velocity and inward acceleration vectors follow an object in circular motion.

Follow two markers at different radii on a spinning or rolling wheel — same ω, different v = rω — with velocity vectors and a cycloid trace.

Give a wheel a constant angular acceleration and scrub time to read θ(t) and ω(t) as rotational analogs of the linear kinematics graphs.

Slide a force along a wrench and tilt its angle to see the lever arm r sin θ and the torque it produces.

Slide point masses along a rod, apply the same torque to two configurations, and compare their angular accelerations.

Race a hoop, disk, solid sphere, and hollow sphere down an adjustable incline with a live energy-bar split between translation and rotation.

Pull a spinning skater’s arms in and out to trade moment of inertia for angular speed while angular momentum stays fixed.

Drop a stationary disk onto a spinning one — the rotational analog of a perfectly inelastic collision, conserving L but not kinetic energy.