1. Forces in MOTION What are simple machines?

2. Machines and Work • A machine is a device that changes the direction or amount of force needed to do work • Simple machines are machines with only a few parts. Examples: pulleys, wheel and axle, inclined plane, and lever • Machines do NOT reduce the amount of work that needs to be done, but rather make it easier to do the work • Since machines allow you to use a smaller amount of force to do the work, the work must be applied at a greater distance. Because of this, the total amount of work stays the same.

3. Types of simple machines • Pulley • Wheel and axle • Lever • Inclined plane

4. Pulley • - consist of a rope or cable that runs through a groovedwheel. • - a pulley makes work easier because it changes the direction of the force needed to do work. • - Examples: flag poles, drapery rods

5. Wheel and Axle • made up of a circular object and a shaft • makes work easier because it reduced the amount of force needed to do work • Examples: a water well and steering wheel of a car

6. Lever • A stiff bar that rotates around a fixed point called a fulcrum • Levers do work by using the stiff bar, the fulcrum, a load, and force you apply • Example: a seesaw changes the direction of the force. When a person uses a seesaw to move a heavy box, the person pushes down but the box goes up. As the position of the fulcrum changes, the amount of force needed to move the box will change. The further the fulcrum is from the person, the easier the lever is to use

7. Inclined plane • An inclined plane is a flat surface with one end higher than the other

8. Complex Machines • A machine that uses 2 or more simple machines is called a complex machine • Complex machines use electricity, gravity, burning fuel, human force, or magnetism to operate the simple machines within it. Many parts combine to make the object move properly.

9. Complex machines • Example: go carts are complex machine but have a wheel and axle (simple machines). • Example: a sailing ship: • Pulleys lift the sails into place • Rudder is a lever • Wheel and axle are used to move the rudder as well as lift the anchor • Oars (which are levers) can be used to move the ship along.

10. Which type of simple machine? Lever

11. Which type of simple machine? Inclined plane

12. Which type of simple machine? Wheel and axle

13. Which type of simple machine? Inclined plane

14. Which type of simple machine? Pulley

15. Which type of simple machine? Inclined plane

16. Which type of simple machine? Wheel and axle

17. What machines can you spy?