Mechanical system basics

Mechanical System Final Exam Study Sheet
A mechanical system is a collection of components that work together to perform a specific
function. These systems range from simple devices, such as handheld tools, to complex
machines, such as automobiles and aircraft. Mechanical systems are ubiquitous in modern
society and are a fundamental part of our daily lives.
Work is movement of a machine
Simple machines:
1. Levers
2. Inclined Plane
3. Wedge
4. Screw
5. Pulley
6. Wheel and axle


LEVERS
Purpose:
● To help move objects
● For recreation
● To help get out of sticky situations


Consist of:
● Bar; free to rotate around a fixed point
● Fulcrum; fixed point of rotation
● Load; mass of object moved or lifted by lever
● Effort force; force you apply to a lever to make it move




Distances on the lever:
Effort arm: distance between the fulcrum and effort force
Load arm: distance between fulcrum and load

, Levers’ classes
● Class 1: fulcrum is between effort, load, weighing balance
● E.g. scissors, seesaw




● Class 2: load is between effort and fulcrum
● E.g. wheelbarrow, door, nail clippers




● Class 3: effort is between load and fulcrum
● E.g. hockey stick, fishing rod, broom, tweezers




Natural levers
- Bones=levers
- Joints=fulcrum
- Tendons; attach muscle to bone
- Load; lifting, bending, pulling




INCLINED PLANE
● Ramp that reduces the force that you need to exert to lift something over a greater distance
● Purpose: for recreation, to help move objects
● E.g. Ramps, stairs, escalators, slides