1. Technological Systems A bicycle is a system of simple machines. It is made up of different components that work together. When we combine simple machines together, we form mechanical systems. Machines usually require inputs (things that enter a system) in the form of energy or matter The machine then does work and a transformation process happens Finally, the machine produces outputs (things that exit a system) in the form of energy or matter

2. Example: the dishwasher Inputs? Dirty dishes Water Electricity Soap Outputs? Clean dishes Waste water Heat Sound energy

3. Simple Machines Create a page size table. Add to your chart as we watch this video and refer to pages 412-417 in your text book. Simple MachineCharacteristics/Function The leverBar rests on a supporting post called a fulcrum. One end has a load that is lifted, on the other end you apply the force. The inclined planeSpread the distance so it is easier to move (lift) something. (ramp) The pulleyChanges the direction of force. When you pull down, the other end goes up. Wheel fitted with a cord (or chain) The wedgeTool used to separate things. It pries something apart. The wheel and axle2 parts wheel and axel. Allows you to move something.

4. Mechanical Systems When simple machines are combined, a MECHANICAL SYSTEM is formed When the same type of motion is transmitted from one component to another without changing form, we call it MOTION TRANSMISSION. When the type of motion changes from one component in a system to another, we call it MOTION TRANSFORMATION.

5. Motion transmission Chain & sprocket

6. Motion Transmission Chain and sprocket Connects components that are far away from one another. The gears do not mesh together; they are connected with a chain (or sprocket) Direction of components The sprockets inside the sprocket will turn in the same direction. ReversibilityYes

7. Motion Transmission Belt & pulley

8. Motion Transmission Belt and pulley system – When building a belt and pulley system, you must ensure: 1.Pulleys must contain a groove where the belt can fit 2.The belt must adhere to the pulleys 3.The smaller the pulley the faster it turns

9. Motion Transmission Gears

10. Motion Transmission Gear trains Contains at least two gears that meet and mesh together Direction of components Alternates from one gear to another ReversibilityYes

11. Motion Transmission Friction wheels

12. Motion Transmission 4. Friction gear systems – Similar to gear trains yet less efficient because the friction gears can slip. – The larger the gear the slower the rotation

13. Motion Transmission p. 419-422 MechanismDescription Chain and SprocketConnect things that are far away from each other (gear and chain).Both sprockets turn in the same direction. Belt and PulleyTwo parts: pulley and belt. Pulleys inside belt go in same direction. Smaller pulleys will rotate faster. GearsThey turn and fit into each other. Each gear goes in the opposite direction. Friction WheelsCircular motion of one turns the other by friction. They are like gears without teeth. PulleyChanges direction of the force. When you pull down, the other end goes up.

14. Motion Transformation Recall: When the type of motion is changed from one component to another in a mechanical system, the motion has transformed.

15. Motion Transformation Systems 1. Rod & Crank

16. Motion Transmission Rod and Crank mechanism – This is the mechanisms used in pistons

17. Motion Transformation Cam & Follower

18. Motion Transformation Cam and Follower – Rotational motion changed to translation motion When building a cam and follower, you must ensure that: 1.The follower must be guided in its translational motion 2.The shape of the cam determines how the follower will move 3.A device such as a return spring is usually necessary to keep the follower in continual contact with the cam.

19. Motion Transformation Rack & Pinion

20. Motion Transformation 1. Rack and Pinion – Contains a rack (straight bar with teeth) and a pinion (gear) While building a rack and pinion you must ensure that: 1.The teeth on the rack and on the pinion must be identical 2.The system requires frequent lubrification 3.The greater the number of teeth on the pinion the slower the rotation

21. Motion Transformation Screw & nut

22. Motion Transformation Screw gear systems (2 Types) – Contains a screw and a nut – Type 1: the screw is the driver Transforms rotational motion into translational motion (e.g. jack to lift the car) – Type 2: the nut is the driver Transforms translational motion into rotational motion

23. Motion Transformation p. 423-425 MechanismDescription Connecting Rod and CrankAlternating to circular motion. Ex: piston in car engine. Cam and FollowerRotational to alternating motion. (Pear shape). Ex: Sewing machine. Rack and PinionRectilinear to circular. Ex: car steering wheel. Screw and NutCircular to rectilinear motion.

24. Discussion Questions What is the difference between motion transmission and motion transformation? Motion transmission is when the same motion changes places. Motion transformation is when the type of motion changes. Give an example of each type of these systems.