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THE PULLEY LAB
REAL PHYSICS · REAL MATH
THEY EXIST FOR A REASON.
PULL WITH YOUR THUMB. FEEL IT BEFORE YOU LEARN THE WORDS.
01 — SINGLE PULLEY
ROPE DOWN · LOAD UP · RIGID 1:1
ROPE PULLED 0 cmLOAD LIFTED 0 cm
LOAD UP = ROPE DOWN
Pull the rope on the right. The box copies your hand — exactly.
02 — COMPOUND PULLEY
TWO WHEELS · 2:1 · HALF THE EFFORT
ROPE PULLED 0 cmLOAD LIFTED 0 cm
PULL 2 → LIFT 1 · FORCE ÷ 2
Pull twice as far. The same box feels half as heavy. That is the trade.
03 — CRANK WINCH
CIRCLES IN · LIFT OUT
TURNS 0.0LOAD LIFTED 0 cm
1 TURN = 2π × DRUM ≈ 19 cm
Grab near the drum and turn clockwise. Circles become lift.
04 — CODE PULLEY
THE ROPE READS CODE · LIVE FROM THIS SITE
LINE 1—
ROPE DOWN = CODE UP · DIAMONDS MARK FUNCTIONS
Pull the rope to read through the real file below.
Tap a diamond to jump to that function.
LOADING /app.js …
06 — GEARS
TEETH THAT MESH · RATIO IS LAW
A 0.0 RPM ·B 0.0 RPM ·C 0.0 RPM ·
RATIO = Ndriven ÷ Ndriver · 12 → 24 → 36
Turn A. B spins half-speed, backwards. C spins third-speed —
forwards again. The idler flips it back. Count the teeth.
07 — SNATCH BLOCK
RIGGING GEAR · ANATOMY · HASP · SEAT · PULL · 2:1
TAP A NUMBERED PART — LEARN ITS NAME. DRAG THE SHACKLE — FEEL THE SWIVEL.
ROPE PULLED 0 cmLOAD MOVED 0 cm
SNATCH BLOCK · OPENS TO TAKE THE ROPE MID-LINE
Tap a numbered part to learn its name. Press the HASP (6) to begin.