Engineering ToolBox - Resources, Tools and Basic Information for Engineering and Design of Technical Applications!

Pendulum

A simple pendulum oscillates in the vertical plane due to gravity.

A simple - or mathematical - pendulum consists of a rigid body suspended from a fixed horizontal axis about which the body may oscillate in a vertical plane due to the action of gravity.

simple pendulum ocillating due to gravity

The oscillating period for a simple pendulum can be calculated as

T = 2 π (l / ag)1/2              (1)

where

T = oscillating period for one cycle (s)

l = length of the pendulum (m, ft)

ag = acceleration of gravity (9.81 m/s2, 32.17 ft/s2)

Example - Calculate the length of a pendulum with an oscillating period of 1 sec, 10 sec and 100 sec

The length of a pendulum with a given oscillating period can be calculated by transforming (1) to:

l = (T / (2 π))2 ag

Length for 1 sec - typically for an old fashion pendulum clock: 

l = ((1 s) / (2 π))2(9.81 m/s2)

  = 0.249 (m)

Pendulum clocks were the world standard for accurate timekeeping for 270 years until the quartz clock was invented in 1927.

Length for 10 sec:

l = ((10 s) / (2 π))2(9.81 m/s2)

  = 24.9 (m)

Length for 100 sec:

l = ((100 s) / (2 π))2(9.81 m/s2)

  = 2487 (m)

Pendelum Oscillating Period chart

Four Types Of Pendulums

It is common to differentiate between four types of pendulums:

  1. Compound or Physical Pendulum - A rigid body suspended from a fixed horizontal axis. The body may oscillate in a vertical plane due to the action of gravity. 
  2. Simple or Mathematical Pendulum - Similar to the compound or physical pendulum but the mass is concentrated in a single point and oscillates back and forth in the vertical plane. The mass point is connected to a horizontal axis with a weightless chord.
  3. Conical Pendulum - Similar to the simple pendulum except that the weight suspended by the chord moves in uniform speed around the circumference of a circle in the horizontal plane.
  4. Torsional Pendulum - A disk fixed to a slender rod. The rod is fastened to a fixed frame. If the disk is twisted it will oscillate back and forth about the axis of the rod.

Related Topics

  • Dynamics

    Motion of bodies and the action of forces in producing or changing their motion - velocity and acceleration, forces and torque.

Related Documents

Search

Search is the most efficient way to navigate the Engineering ToolBox.

Engineering ToolBox - SketchUp Extension - Online 3D modeling!

3D Engineering ToolBox Extension to SketchUp - add parametric components to your SketchUp model

Add standard and customized parametric components - like flange beams, lumbers, piping, stairs and more - to your Sketchup model with the Engineering ToolBox - SketchUp Extension - enabled for use with older versions of the amazing SketchUp Make and the newer "up to date" SketchUp Pro . Add the Engineering ToolBox extension to your SketchUp Make/Pro from the Extension Warehouse !

Translate this Page

Translate this page to Your Own Language .

About the Engineering ToolBox!

Privacy Policy

We don't collect information from our users. More about

We use a third-party to provide monetization technologies for our site. You can review their privacy and cookie policy here.

You can change your privacy settings by clicking the following button: .

Citation

This page can be cited as

  • The Engineering ToolBox (2012). Pendulum. [online] Available at: https://www.engineeringtoolbox.com/pendulum-d_1836.html [Accessed Day Month Year].

Modify the access date according your visit.

3D Engineering ToolBox - draw and model technical applications! 2D Engineering ToolBox - create and share online diagram drawing templates! Engineering ToolBox Apps - mobile online and offline engineering applications!

Unit Converter

















































4.10.13

.