Mechanisms are the basic components of most machines and consist of gears, sprockets, pulley systems, and simple machines. The effective use and understanding of mechanisms has contributed to the improvement and development of technology and society for thousands of years. The first uses of mechanisms can be seen in the development of Paleolithic tools used for hunting, gathering, and shelter construction. Today mechanisms can be found in everyday life from the basic components of a bicycle to the high-tech equipment used in the medical industry.


Engineers and scientists use mechanisms to manipulate speed, distance, force, and function to meet a wide range of design and application requirements. Engineering design applications can range from large-scale manufacturing equipment to small-scale electrical equipment found in automobiles, homes, and offices. Due to the wide range of applications involving mechanisms, it is important that designers and end users understand the characteristics, applications, and limitations of mechanisms.   


In Lesson 1.1 Mechanisms, you will gain an understanding of mechanisms through the application of theory-based calculations accompanied by lab experimentation.

K1 – Know the six simple machines, their attributes, and components.
K2 – Know the equations to solve for mechanical advantage, work, and power.

K3 – Know how gears work, including compound gears, pulley drives and chain drives.

S1 – Measure forces and distances related to mechanisms. 
S2 – Distinguish among the six simple machines, their attributes, and components. 
S3 – Calculate mechanical advantage of mechanisms. 

S4 – Calculate gear ratios, torque and angular speed of various gear assemblies.
S5 – Design, create, and test systems using simple machines and drive mechanisms. 
S6 – Calculate work and power in mechanical systems. 
S7 – Determine efficiency in a mechanical system. 
S8 – Design, create, test, and evaluate a compound machine design.
S9 – Communicate a design for a machine using annotated sketches and other documentation. 
S10 – Collaborate effectively with others in a design team.

Recommended Reading: Basic Machines and How They Work, Prepared by the Naval Education and Training Program Development Center (Dover Publications, Inc.)






The Six Simple Machines, Ideal Mechanical Advantage and Work - website

The Six Simple Machines and Calculating (Ideal) Mechanical Advantage (sample problems) - archived webpage (pdf) (

The Six Simple Machines (again) and the difference between Ideal and Actual Mechanical Advantage - pdf (on Google Drive) 

A Simple Machines Identification Game - website

Pulleys - website (see the section on Pulleys and Lifting; Pulley [Drive] Systems will be grouped with Gears)

An Entertaining Essay on Pulleys - website

Notes and Practice Calculations (for work, IMA, AMA and efficiency) with Inclined Planes - worksheet 1worksheet 2 (on Google Drive)


An Introduction to the VEX Robotics Design System (our hardware) with notes on Gears and Belt Drives - pdf (on Google Drive)

Instructions for Building a Device incorporating all the Simple Machines - pdf (on Google Drive)

Data Sheet to accompany the Simple Machine Device (Activity 1.1.1) - pdf (on Google Drive)

Notes and Practice Problems on Work, MA and Efficiency - pdf (on Google Drive)





Gears - website

Gears, Gear Trains, Compound Gears, Gear Ratios, and Pulley Systems - website (this is the same website referenced above for Pulleys)

Gears and Gear Ratios - PowerPoint as pdf (on Google Drive)

Gears and Gear Ratios - website

Gear Ratios, with a focus on VEX Gears - website

Gear Types - YouTube video (watch through 16:23; the remainder of the video is informative but unnecessary)

Gear Ratios and Compound Gear Ratios, with a YouTube video showing the making of clock gears  - website

Gear Ratios and Bicycles - YouTube video

How a Car's Manual Transmission Gearbox Works - YouTube video

How a Car's Differential Gear Works (which enables turning by allowing the wheels to spin at different rates) - YouTube video

Gear Problem Set - pdf (on Google Drive)


Compound Machines - pdf (on Google Drive)

Compound Machine Mechanical Advantage Example - illustration (on Google Drive)

Compound Machine Design Challenge - pdf (on Google Drive) - design a machine to assist someone with a physical disability (e.g. a machine to open a Coke can, or place an object on a high shelf, or turn on a light, etc.)


Get help calculating IMA, AMA, work and efficiency for various simple machines.

(Here are the problems I solved in the video.)

Demonstration of a compound machine. 3rd period. 2015.

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