第一原理の物理実験室 · The first-principles physics lab
Physics, drawn from first principles.
Turn a spectrometer telescope and read its vernier. Ramp a Franck–Hertz tube until the mercury glows. Release a pendulum and time it with a photogate. Every experiment here is computed live from the equations of nature, in your browser.
学問の道 · Paths of study
Every experiment, sorted by branch of physics
Pick a branch to see its experiments. Branches marked “soon” are being built, and new experiments are added regularly.
おすすめ · Start here
Featured experiments
Each preview below is the real simulation, running at miniature scale.
三つの原則 · Three principles
Built like a laboratory, checked like research code
- 一
Computed, never animated
Motion comes from integrating the governing equations (Runge–Kutta, split-step Fourier, FDTD, exact Hamiltonians), not from keyframes. Change a parameter and nature answers.
- 二
Real instruments
Verniers, micrometers, photogates and oscilloscopes are drawn in code and behave like the real thing, including backlash, finite resolution and noise.
- 三
Honest results
Every measurement carries its uncertainty. Weighted fits, χ² and propagation of error are done properly, and results are compared with NIST and CODATA values.
新着 · Recently added
New in the lab
目録 · Directory
Every experiment at a glance
力学 Classical Mechanics
- Simple Pendulum: Lagrangian & Elliptic PeriodNon-linear pendulum dynamics with photogate timer, phase portraits, and exact Legendre elliptic integral period expansion.
- Double-Pendulum ChaosDeterministic chaos in coupled pendula with Hamiltonian energy conservation monitoring (drift < 3×10⁻¹¹).
- Ballistic Pendulum: Momentum & EnergyMeasure projectile muzzle velocity by inelastic collision with a suspended catcher, cross-checked against free flight.
- Torsion Pendulum & Moment of InertiaDetermine wire shear modulus and body moments of inertia while verifying Steiner's parallel-axis theorem.
- Hooke's Law & Coupled Harmonic OscillationsExplore coupled carts on an air track, normal in-phase and anti-phase modes, and periodic energy exchange beats.
- Moment of Inertia of a FlywheelDetermine the rotational inertia of a heavy flywheel from falling mass potential energy and bearing friction coasting turns.
- Kepler's Laws of Planetary MotionPlanetary and cometary orbits with equal-area sector sweeps, vis-viva velocity, and solar system harmonic law verification.
光学 Waves & Optics
- Maxwell Wave Lab (2D FDTD)Electromagnetic wave propagation, double-slit diffraction, dielectric refraction, and wavepacket scattering.
- Speed of Light: Rotating Mirror MethodTerrestrial speed of light measurement using a high-speed octagonal turbine mirror and folded long-distance optical baseline.
- Beer–Lambert Law & PhotometrySerial dilution series, spectrophotometer blank calibration, and chemical concentration determination.
電磁 Electromagnetism
- Electric Fields & PotentialsInteractive charge placement, vector field streamlines, and live voltmeter probe potential measurement.
相対 Special Relativity
- Addition of Relativistic VelocityTest Einstein velocity composition, observe the light cone boundary, and verify that no physical speed can exceed c.
量子 Quantum Physics
- Wavepackets & Quantum TunnellingLive quantum wavepacket evolution with barrier penetration, evanescent decay, and transmission probability T.
- Photoelectric Effect & Planck's ConstantSpectral filters on a vacuum photocell, linear V₀ vs. ν regression, yielding Planck’s constant within 0.2%.
原子 Atomic Physics
- Rydberg Constant (Balmer Series)Rotate spectrometer telescope, read dual vernier scales, and fit the 1/λ line to determine R_H within 0.05%.
- Sodium Fine Structure (Michelson)Count Haidinger circular interference fringes and track visibility beats to resolve the 0.597 nm D1/D2 doublet split.
- Helium Spectrum: Para & OrthoInteractive Grotrian transition diagram, Rydberg-Ritz quantum defects, and exchange interaction splitting.
- Moseley's Law (X-Ray Fluorescence)Excitation of 30 pure metal foils with 35 kV X-rays, Gaussian multichannel analyzer fitting, and Moseley plot.
- Franck–Hertz ExperimentAccelerating voltage ramp with periodic current dips every 4.89 V in Hg, and glowing excitation layers in Ne.
分子 Molecular Spectroscopy
- HCl Rovibrational Infrared (FTIR)Resolve the P- and R-branch lines of H³⁵Cl and H³⁷Cl, fit rotational constants B₀ and B₁, and extract bond distance r_e.
- Raman SpectroscopyLaser Raman scattering of CCl₄, benzene, and cyclohexane; verify Boltzmann temperature from peak ratios.
- Iodine Absorption & DissociationVibrational band head absorption of I₂ vapor, linear Birge–Sponer extrapolation to the convergence limit.
共鳴 Magnetic Resonance
- Electron Spin Resonance (DPPH)RF modulation of DPPH in calibrated Helmholtz coils; trace resonance dips on oscilloscope to determine Landé g-factor.
- Proton NMR SpectroscopyPulsed NMR with FID signal processing, phase correction, integration, and ethanol triplet-quartet multiplet analysis.
計算 Computational Physics & Data
- Physics-Informed Neural Networks (PINN)Deep neural networks solving partial differential equations live without spatial meshes using exact automatic differentiation.
- Lab Data Plotter & Error CalculatorUpload raw laboratory CSV readings to perform weighted fits, propagate covariance uncertainties, and generate publication graphs.
縁 · Community
Learn together. Shape what comes next.
Ask questions, share your results and vote on the next experiments in the community forum. Teachers and institutions can write to us about classroom use and licensing.