1. Machines 4. Simple Machines

2. Simple Machines

3. There are thousands of different kinds of machines
You use machines every day

4. A device that makes work easier
But did you know that all machines are based on only six (6) kinds of simple machines
Vocabulary:
Simple machines
A device that makes work easier

5. A lever is one type of simple machine
Vocabulary:
lever
A rod that can turn on a point called a fulcrum

6. A point on which a lever can turn
Vocabulary:
fulcrum
A point on which a lever can turn

7. If you push down on the end of one kind of lever
The other end moves up

8. You can lift things more easily because less force is needed

9. There are three (3) basic kinds of levers
They are different because each kind has the fulcrum in a different place

10. The fulcrum is between the load force and the effort force
First class lever:
The fulcrum is between the load force and the effort force

11. The load force is between the effort force and the fulcrum
Second class lever:
The load force is between the effort force and the fulcrum

12. The effort force is between the fulcrum and the load force
Third class lever:
The effort force is between the fulcrum and the load force

13. An inclined plane is a flat surface that slopes
Vocabulary:
Inclined plane
A flat surface that slopes

14. A board from a low place to a high place is an inclined plane
called a ramp

15. Less force is needed to slide an object up a ramp
than to lift the object

16. A wedge can split a log more easily by hitting a wedge stuck in the log

17. Two inclined planes that come together at a point
Vocabulary:
wedge
Two inclined planes that come together at a point

18. A screw is an inclined plane wrapped around a rod
Screws hold things together better than nails

19. You can fasten an object to one end of the rope on a pulley
If you pull the other end,
you can lift the object

20. A wheel with a rope around it and is used to lift objects
Vocabulary:
pulley
A wheel with a rope around it and is used to lift objects

21. 3 Basic Types of Pulleys:
Fixed Pulley
Mechanical Advantage is 1
If you are lifting 150 pounds you have to apply 150 pounds force

22. Mechanical Advantage: Count number of rope sections
NOTE: Subtract 1 if you have to pull down on rope
2 ropes pieces
1 you use to pull down to apply force
Mechanical Advantage: 1

23. Mechanical Advantage is 2
Moveable Pulley
Mechanical Advantage is 2
If you are lifting 150 pounds you have to apply 75 pounds force

24. Combined Pulley Mechanical Advantage is 2
Count number of rope pieces
Subtract 1 since pulling down
Mechanical Advantage is 2
If you are lifting 150 pounds you have to apply 75 pounds force

25. Combined Pulley Mechanical Advantage is 3
Count number of rope pieces
Pulling up so it counts
Mechanical Advantage is 3
If you are lifting 150 pounds you have to apply 50 pounds force

26. Several pulleys can be joined together
Count number of rope pieces
Subtract 1 since pulling down
Mechanical Advantage is 3
to make it easy to lift heavy objects

27. Identify the mechanical advantage in each set of pulleys:
MA ?
MA ?
MA ?

28. A wheel and axle is really a kind of lever
that continues to turn around its fulcrum