1. 1. Simple Machines Objectives: -Identify the kinds of simple machines. -Give examples of simple machine.
2. 2. These are simple device that affects the force, or effort, needed to do a certain amount of work. Simple Machines
3. 3. Machines can make a tough job seem easier by enabling a person to apply less force or to apply force in a direction that is easier to manipulate. Simple Machines
4. 4. Machines lessen the force needed to perform work by lengthening the distance over which the force is applied. Simple Machines
5. 5. Machines can also increase the speed at which work makes an object travel, but increasing speed requires the application of more effort. Simple Machines
6. 6. Types of simple machine A. Inclined Plane is a simple machine, consisting of a ramp or a similar wedge-shaped device, that makes doing a given amount of work easier. Simple Machines
7. 7. An inclined plane makes it easier to lift heavy objects by enabling a person to apply the necessary force over a greater distance. Simple Machines
8. 8. Example of inclined plane: Simple Machines
9. 9. Simple Machines B. Lever is a simple machine consisting of a rigid bar that rotates about a fixed point, called a fulcrum.
10. 10. Simple Machines Types of Lever 1. Class 1 Levers - has the fulcrum between the force and the load, as in a seesaw.
11. 11. Example of class 1 lever Simple Machines
12. 12. Simple Machines 2. Class 2 Levers - has the fulcrum at one end, the force at the other end, and the load in the middle.
13. 13. Simple Machines 3. Class 3 Levers - has the fulcrum at one end, the load at the other end, and the force in the middle.
14. 14. Simple Machines C. Pulley, simple machine used to lift objects. A pulley consists of a grooved wheel or disk within a housing, and a rope or cable threaded around the disk.
15. 15. Simple Machines Pulleys are used for lifting by attaching one end of the rope to the object, threading the rope through the pulley (or system of pulleys), and pulling on the other end of the rope.
16. 16. Simple Machines Example of a pulley found on fishing boat
17. 17. Simple Machines D. Wedge is another form of inclined plane. A wedge is essentially a double inclined plane, where two planes are joined at their bases.
18. 18. Simple Machines Wedges transfer downward effort applied to the blunt edge of the wedge out to the sides of the wedge to help it cut through an object.
19. 19. Simple Machines Example of wedge:
20. 20. Simple Machines E. Wheel and Axle is a simple machine, consisting of a circular objectthe wheelwith a shaftthe axlerunning through and attached to the center of the wheel.
21. 21. Simple Machines Example of wheel and axle
22. 22. Simple Machines F. Screw is a mechanical fastening device consisting essentially of an inclined plane wound spirally around a cylinder or a cone.
23. 23. Simple Machines The ridges formed by the winding planes are called threads, and depending on the intended use, the threads may be square, triangular, or rounded in cross section.
24. 24. Simple Machines Example of screw
25. 25. References: The world of Science 5 Into the Future; Science and Health 5 BEC Handbook in Science 5 Encarta 2009