Free Fall Race — Free Online Terminal Velocity & Drag Force Game
Free Fall Race is a prediction game — make your call about which object lands first, then watch the real physics play out. Each object's motion is governed by F = ma with drag force F_d = ½ρC_dAv² applied every frame.
The physics behind the game
Free fall in vacuum
With no air resistance, every object accelerates identically. A feather and a cannonball hit the ground at the same time — Galileo proved this, Apollo 15 demonstrated it on the Moon.
Drag force
Air resistance grows with the square of velocity. Once drag force equals weight, acceleration reaches zero — this is terminal velocity. Bigger cross-section and higher drag coefficient both increase drag.
Terminal velocity
The maximum speed of a falling object. Heavy objects and small cross-sections give high terminal velocity. Light objects with large cross-sections (like a parachute) have very low terminal velocity.
Stokes' drag (slow flow)
For very slow flows or small objects (like dust particles, fog droplets), drag is proportional to velocity not velocity squared. This is Stokes' law.