1. Chapter 14 Section 1: Work and Power
Objective: Student will learn how to compute work and power.

2. Work
Work is done when a force causes an object to move in the same direction that they force is applied.
Draw/ write the captions for figure 2 on page 427.
The equation for finding work is
Work (in joules) = force (in newtons) x distance (meters)
W=Fd

3. Power Power is rate at which work is done. The equation for power is
Power ( in watts) = work (joules)/ time (seconds)
P= W/t

4. Chapter 14 Section 3: Using Machines
Objective: Student will learn all the types of simple machines and how they move.

5. Simple Machine
A simple machine is a machine that does work with only one movement.
A machine made up of a combination on simple machines is a compound machine.
There are six simple machines: inclined plane, lever, wheel and axle, screw, wedge, and pulley.

6. Inclined Plane An inclined plane is a flat, sloped surface.
Less force is needed to move an object from one height to another using an inclined plane.
Examples: ramps, hills

7. Wedge An inclined plane that moves is a wedge.
Examples: knives, axes, teeth

8. Screw
A screw is an inclined plane wrapped around a post or a cylinder.
Friction between the threads allows for objects to “hold.”

9. Lever
A lever is an rigid rod or plank that pivots, or rotates, about a point.
The point about which the lever pivots is called a fulcrum.
Examples, see saws, crowbar, spatula

10. Wheel and Axel
A wheel and axel is two circular objects of different diameters attached so that they rotate together.
Examples: water faucets, rotary telephone, rolling pin, pencil shapener

11. Pulley
A pulley consist of a grooved wheel with a rope or cable wrapped over it.
Example: flag pole, blinds, curtain on window