Pendulum Period Calculator

Calculate the period and frequency of a simple pendulum for small and large angle oscillations

Calculate Pendulum Period

Distance from pivot point to center of mass

Standard Earth gravity: 9.81 m/s²

Pendulum Period Results

2.0061
Period (seconds)
0.4985
Frequency (Hz)
3.1321
Angular Frequency (rad/s)

Formula used: T = 2π√(L/g)

Input values: L = 1.000 m, g = 9.81 m/s²

Note: Small angle approximation is valid for angles ≤ 15°

Period Analysis

✅ Typical pendulum period - good for clock mechanisms

Example Calculations

Standard Grandfather Clock

Length: 1.0 meter

Gravity: 9.81 m/s² (Earth)

Period: T = 2π√(1.0/9.81) = 2.006 seconds

Note: Perfect for "tick-tock" every second

Foucault Pendulum (Large Angle)

Length: 67 meters (Panthéon, Paris)

Initial angle: 30°

Small angle period: 16.6 seconds

Exact period: ~17.2 seconds (+3.6% correction)

Gravity Values

Earth (average)9.81 m/s²
Earth (poles)9.83 m/s²
Earth (equator)9.78 m/s²
Moon1.62 m/s²
Mars3.71 m/s²
Jupiter24.79 m/s²

Pendulum Facts

Period is independent of mass and amplitude (small angles)

Longer pendulums have longer periods

Higher gravity leads to shorter periods

Large angles require exact formula for accuracy

Used in clocks, seismometers, and experiments

Understanding Pendulum Period

What is a Simple Pendulum?

A simple pendulum consists of a point mass (bob) suspended from a fixed point by a massless, inextensible string or rod. The bob oscillates back and forth under the influence of gravity, creating periodic motion.

Key Properties

  • Period depends only on length and gravity (small angles)
  • Independent of mass and initial amplitude
  • Exhibits simple harmonic motion for small angles
  • Period increases with larger initial angles

Mathematical Formulas

Small Angle Approximation (θ ≤ 15°)

T = 2π√(L/g)

Simple and accurate for small oscillations

Exact Formula (Any Angle)

T = 2π√(L/g) × K(sin(θ₀/2))

Uses elliptic integral for large angles

Note: For angles > 15°, the exact formula provides significantly more accurate results.

Historical Applications

Timekeeping

Pendulum clocks were the most accurate timekeepers for over 300 years, from their invention by Christiaan Huygens in 1656 until the 1930s.

Gravitational Studies

Pendulums were used to measure local gravitational acceleration and detect variations in Earth's gravity field across different locations.

Foucault Pendulum

Demonstrates Earth's rotation through the apparent precession of the oscillation plane, providing direct evidence of our planet's motion.

Seismology

Early seismometers used pendulum mechanisms to detect and record earthquakes and other ground vibrations.