Pendulum Simulator

Adjust length, gravity, initial angle and damping; watch the pendulum swing and read the period live.

Period (small-angle)
Frequency
Angle
Angular speed
Elapsed

Formula

Small-angle period: T = 2π · √(L / g)
Full equation of motion: θ̈ = −(g/L)·sin θ − b·θ̇

Physics behind the pendulum

A simple pendulum is the canonical example of simple harmonic motion. For small angles, sin θ ≈ θ and the system oscillates with period T = 2π√(L/g). At larger angles the period grows slightly (up to a few percent at 30°, more at larger angles). This simulator uses the full non-linear equation of motion integrated with a symplectic velocity-Verlet scheme, so big-angle behaviour is physically correct. Damping b models friction and air resistance.

Worked example

L = 1 m, g = 9.80665

T = 2π · √(1/9.80665) ≈ 2.006 s

Related tools

Angular Velocity Free Fall Wave Interference

FAQs

Small-angle period?

T = 2π·√(L/g).

Does mass affect it?

No — length and gravity only.