Teacher’s Notes POS IMC videos/POS Computer research project Unit Research project

Program of Studies Simple machines Systems and Subsystems Analyze machines by describing the structures and functions of the overall system, the subsystems and the component parts analyze a mechanical device, by: describing the overall function of the device describing the contribution of individual components or subsystems to the overall function of the device identifying components that operate as simple machines

Videos illustrate how a common need has been met in different ways over time (e.g., development of different kinds of lifting devices) illustrate how trial and error and scientific knowledge both play a role in technological development (e.g., development of aircraft)

Excellent Videos Simple Machines VT06562 Inclined Plane, Wedge Screw VT06563 Lever, Wheel and Axle, Pulley Includes mechanical advantage (caveman videos)

Inclined plane gizmo http://www.explorelearning.com/index.cfm?method=cExtAccessSecure.dspResource&ResourceID=649&certificate=authorizer%3DLearnAlberta%26userid%3DLA05%26i%3D0%26expires%3D2013%252F04%252F11%2B09%253A07%253A19%26hash%3DR8BXNikiaailDDHNWqBhEA%253D%253D

Computer Research Project POS• investigate and provide examples of mechanical devices used in the past to meet particular needs (e.g., describe and interpret devices developed to move water or be moved by water, such as the Persian wheel, Archimedes’ screw, mill wheel)

Unit Project Mouse trap car Mouse trap catapult Rube Goldberg “Mouse-trap” project *Sample provided in blue book Title page/labeled diagram Log book Structure (either brought in or videotaped)

Lesson 1 Simple and Complex Machines

Simple Machines Machines are devices that meet human needs, using energy more effectively. Make work faster Make work easier Change the direction of a force Design is usually related to the function See if you can figure out the function for each “old fashioned” machine

Mill wheel

Aqueduct (Roman)

Archimedes’ screw/modern grain auger

Da Vinci’s helicopter

Simple Machines *handouts+ brainpop There are 6 Levers (class 1,2,3) Pulleys Wheel and Axle Inclined Plane Wedge Screw

A lever is made up of 3 parts: Fulcrum: pivot point Load Force Effort Force Three types: Class 1 Class 2 Class 3

Levers

Lever examples

Inclined Plane

Wedge Made up of one or two inclined planes Function: to push objects apart Exception: nails Wedge

Wedge examples Door jam Axe Knife Scissors Nail Turns a downward force into a sideways force

Screw Inclined Plane wrapped around a cylinder Tighter threads = greater mechanical advantage

Wheel and Axle Depending on whether you spin the axle or the wheel: -Turning the axle gives a speed advantage (more energy required) ex: car -Turning the wheel gives a mechanical advantage (easier to turn) Ex. Key, doorknob, faucet, screwdriver

Pulley Changes the direction of the force Add pulleys in pairs to reduce the effort force for a block and tackle system

Mechanical Systems 1.1 Simple Machines

Simple Machines Machines help people use energy more efficiently. A machine helps us do work. The earliest machines were simple devices to make work easier; like moving a large rock or moving a load up an incline, splitting wood or lifting materials up to a working area above the ground. These simple machines depended on people or animals as their source of energy.

Levers A lever is a rigid bar or plank that can rotate around a fixed point called a pivot, or fulcrum. Levers are used to reduce the force need to do a particular task. You can move a very large load, but you must move a greater distance than the load moves.

Levers FIRST CLASS LEVER The fulcrum is between the load force (FL) and the effort force (FE). eg: a teeter totter

Levers cont… SECOND CLASS LEVER The load force (FL) is between the effort force (FE) and the fulcrum. eg: a wheel barrow THIRD CLASS LEVER The effort force (FE) is between the fulcrum and the load force (FL). eg: tweezers, your arm

Inclined Plane Inclined plane or ramp makes it easier to move a load higher than it is, but it has to be moved over a much longer distance. An inclined plane makes it possible to lift heavy objects using a smaller force (examples: loading ramp, wheelchair access ramp)

Wedge Wedge is similar in shape to an inclined plane, but is used in a different way (and can only be used in one direction). It is forced into an object to split it apart. The wedge increases the force applied to the object, but it moves a greater distance into the object than it splits apart.

Screw A Screw is a cylinder with a groove cut in a spiral on the outside. (It is actually an inclined plane that winds around itself) It can be used to convert rotational (turning) motion to linear motion (movement in a straight line). It moves objects in a straight line very slowly.

Pulley A pulley makes work seem easier because it changes the direction of motion to work with gravity. Instead of lifting up, you can pull down using your body weigh against the resistance (load, that you are lifting).

Wheel and Axle The Wheel and Axle is a combination of two wheels of different diameters that turn together. A lever that rotates in a circle around a center point or fulcrum. A longer motion on the wheel produces a more powerful motion on the axle. They can be used to increase the size of the force (steering wheel in a car) or the speed (bicycle wheels).

Complex Machine: Complex machines or systems are made up of subsystems, or simple machines Each subsystem will contribute to the device’s function Analyze the pencil sharpener and bike. What are the functions of each piece? Can you identify the simple machines?

Bicycle

Pencil Sharpener

Simple Machines- supplementary notes (link on eboard) http://www.worsleyschool.net/science/files/simple/machines.html http://images.google.com/imgres?imgurl=http://www.edinformatics.com/math_science/simple_machines/180px-Polispasto2.jpg&imgrefurl=http://www.edinformatics.com/math_science/simple_machines/pulley.htm&h=288&w=180&sz=9&hl=en&start=10&tbnid=oonTI6nxfYam3M:&tbnh=115&tbnw=72&prev=/images%3Fq%3Dpulley%26svnum%3D10%26hl%3Den%26safe%3Doff%26client%3Dsafari%26rls%3Den-us%26sa%3DG Goes through and does a good job of explaining simple machines (there are many more, just type it in google

Design and Function

POS identify the source of energy for some familiar mechanical devices evaluate the design and function of a mechanical device in relation to its efficiency and effectiveness, and identify its impacts on humans and the environment

Activity Page 276-How many machines are in your home? Make a list of machines in and around the home, Describe the task Source of energy Short story on what life would be like without all these machines

Machine Task/Function Source of Energy

Computer assignment “Old school machine” project Students become comfortable using tables in word and inserting images

Assignments “What is a simple machine” worksheets (solutions on overheads) Demo of force advantage depending on fulcrum location of 1st class lever “Levers have class” worksheet also label F-L-E for each Section 1.0 Questions Pg 268 #1-4 Pg 276 #3 Pg 277 #2,3,4

Activity/Lab Pg 256 Science in Action: Page 265 Sia Remove robotic probe from hole (design) Page 265 Sia The Right Machine for the job Lifting without, with pulley, with ramp, with lever

Section 1.0 Pop Quiz Draw a diagram and label the three classes of levers FLE Give an example of each List the other 5 simple machines