Physics Lab

Simulations

Everything runs client-side in plain JavaScript on a canvas — no plugins, no accounts, nothing sent anywhere. Each simulation exposes the physical parameters directly, so the interesting thing to do is push them until the model breaks and see whether it breaks the way the theory says it should.

• Mechanics

  Projectile & orbital motion

  The same inverse-square force, twice. Near the ground it is a constant g fighting quadratic air drag, and the textbook parabola overshoots badly. Far from it the air is gone, the force falls off as 1/r², and the orbit closes on itself — provided the integrator respects the geometry.

  • RK4
  • Velocity Verlet
  • Quadratic drag
  • Two-body
  Open simulation
• Equation of state

  Pressure, volume & temperature

  One equation, PV = nRT, and the three laws usually taught as if they were three. Clamp one variable and drive a second, or take the box yourself: set any two, drag the piston, and go where you like. Boyle, Charles and Gay-Lussac turn out to be slices of one surface — so the surface is drawn, and van der Waals runs alongside to show where the whole idea fails.

  • 4 processes + sandbox
  • draggable piston
  • ∫P dV vs closed form
  • van der Waals
  • P–V–T surface
  Open simulation
• Kinetic theory

  Ideal gas particle box

  Argon atoms as hard discs in a nanometre box with a movable piston. Nothing here assumes PA = Nk_BT — the pressure is measured from the momentum the atoms actually deliver to the walls, and the gas law comes out of the collisions.

  • 2-D molecular dynamics
  • Hard-disc collisions
  • Maxwell–Boltzmann
  Open simulation
• Heat transfer

  Transient heat conduction

  A rod with one end clamped hot and the other end fixed, insulated or blown on. Crank–Nicolson in time, control volumes in space, real material properties, and a first-law energy ledger that has to balance.

  • Crank–Nicolson
  • Control volumes
  • Fourier & Biot
  Open simulation
• Thermodynamics

  Heat engines & the second law

  A fixed mass of ideal gas walked around a closed cycle — Carnot, Otto, Stirling or Brayton — with every joule accounted for. The P–V and T–S areas are computed numerically and compared, and the entropy generated per cycle sits next to the efficiency. Nothing is allowed to beat Carnot.

  • 4 cycles
  • P–V & T–S
  • Entropy generation
  Open simulation

About the lab

These pages are a by-product of engineering practice, not a teaching product. Each one was built to check an intuition against a numerical answer, and they are published here because a simulation you can push on is a better argument than a formula on a slide.

No warranty of fitness for design work. The models are simplified — idealised gases, one-dimensional conduction, two-body gravity, no radiation — and they are not a substitute for the codes and standards that govern real engineering. Nothing here should be used as the basis of a design, a calculation of record, or a safety decision.

Questions or corrections are welcome at [email protected].