Pendulum Park

Each pendulum's swing period depends on its length. Adjust each rod so its swing lands on the beat, lining the chimes up in time, effectively solving T = 2π·√(L/g) by feel and ear.

• Drag a slider to change a rod's length
• Longer rods swing slower; shorter rods swing faster
• Match each pendulum to the target ring on the beat marker
• Get every chime swinging in time to finish the park

• 2, 3 or 4 chimes for increasing difficulty
• Daily park or Practice for fresh setups

• Desktop: drag the length sliders; toggle Sound to hear the beat
• Phone & tablet: drag sliders with a finger and tap Sound

• Tune the slowest, longest pendulum first and build the others around its beat
• Period grows with the square root of length, so big swings need big length changes
• Trust your ears, when the chimes click into rhythm you're on the target

Pendulum Park is a rhythm puzzle built on the physics of pendulums, where length sets the period you have to time.

• Skills: pendulum motion, period and length, periodic motion, timing
• Best for: roughly grades 7–11 (ages 12–16)
• For parents & teachers: shows the surprising rule that a pendulum's period depends on length, not weight.

Tuning rods so their chimes land on the beat is solving T = 2π√(L/g) by ear — the period of a pendulum.

Doing it by feel rather than by calculation is the original method.

The formula's strangest feature becomes audible this way: period depends on length and not at all on mass, and it goes as the square root, so quadrupling the length only doubles the period. Tuning by ear makes that square root something you discover rather than accept.

Pendulum Park is a physics rhythm puzzle about pendulum period and length. It's an original, free browser game made in-house for PlayPendium.

A free, original browser game on PlayPendium. No download, no install.