1. Simple Machines & Mechanical Advantage RHS Technology Education

2. Simple Machines are Designed to… Transfer kinetic energy (the energy of motion) Reduce the effort needed to move a load Change the direction or amount of motion Change the type of motion (rotary to straight line)

3. Mechanical Advantage What is Mechanical Advantage? a measure of how much the effort is decreased by the simple machine. Ideal Mechanical Advantage (IMA) ignores internal friction How do I calculate IMA? IMA=Effort distance/Resistance distance

4. Lever A lever is a stiff bar which rotates around a point called the fulcrum. Can you list some examples of a lever?

5. 1 st Class Levers

6. 2 nd Class Lever

7. 3 rd Class Lever

8. Mechanical Advantage of Lever IMA= Effort Arm (Effort to Fulcrum)/Resistance Arm (Resistance to Fulcrum)

9. Wheel and Axle A Wheel & Axle change rotary motion into linear motion IMA= Wheel Radius/ Axle Radius

10. Fixed Pulley Movable Pulley Block & Tackle The Three Types of Pulleys

11. Pulley IMA = is determined by counting the number of supporting ropes Last one over top does not count!

12. Inclined Plane IMA= Length of Slope/ Height of the Slope

13. Wedge IMA= Length of Sloped Edge / Separation Surface

14. Effort Inclined Plane Effort Wedge Inclined Plane vs. Wedge

15. Screw A screw works by using a twisting motion to create torsion

16. Screw IMA= 3.14x Diameter/ Distance between threads (lead)

17. Practice Problem Calculate the mechanical advantage of the screw shown In this example: The diameter is (1/4)” The lead is 1/20 What is the IMA of this screw?