1. Simple
Machines

2. What are the 6 simple
machines?
•
•Wedge
•Screw
Inclined plane
•
Wheel & Axle
•
•Pulley
Lever

3. MACHINE
• Def: A device that allows you to
do work in a way that is easier.
• Sent.: They have agreed to rely
primarily on the use of the six
simple machines to accomplish
their mission.

4. MACHINE
•
• Discuss in your group different
Sp: máquina
machines.

5. HOW DOES A MACHINE
MAKE WORK EASIER?
• Change the amount of force you
exert
• Change the distance over which
you exert your force.
• Change the direction in which you
exert your force.

6. INPUT FORCE
• Def.: The force exerted on a machine
• Sent.: Machines such as the car jack, the
ramp, the crow bar, and the claw hammer
make work easier by making the output
force greater than the input force.
• Sp.: fuerza aplicada

7. OUTPUT FORCE
• Def.: The force exerted on an object by a
machine.
• Sent.: Machines such as the car jack, the
ramp, the crow bar, and the claw hammer
make work easier by making the output
force greater than the input force.
• Sp.: fuerza desarrollada

9. INPUT WORK
• Def.: The work done on a machine as the
input force acts through the input
distance.
• Sent.: For such an ideal machine, the input
work would equal the output work.
• Sp.: trabajo aportado

10. OUTPUT WORK
• Def.: The work done by a machine as the
output force acts through the output
distance.
• Sent.: For such an ideal machine, the input
work would equal the output work.
• Sp.: trabajo producido

11. MECHANICAL
ADVANTAGE
• Def.: Number of times a machine
increases a force exerted on it.
• Sent.: The mechanical advantage of a
machine without friction is called the
ideal mechanical advantage, or IMA.
• Sp.: ventaja mecánica

12. Mechanical Advantage =
Output force ÷ Input force

13. If the machine increases
force then the mechanical
advantage will be greater
than 1.

14. If the machine increases
distance then the mechanical
advantage will be less than 1.

15. If the machine changes the
direction then the
mechanical advantage will be
1.

16. Simple Machines

17. Inclined Plane

18. Inclined Plane
• Def.: Flat, sloped surface
• Sent.: An inclined plane allows you to
exert your input force over a longer
distance.
• Sp.: plano inclinado
• Discuss with your table different types
of ramps.

19. Inclined Plane
• How it works: increases the distance the
input force has to go.
• IMA = length of incline ÷ height of
incline

20. Direct Relationship
• Def.: When both variable either increase
or decrease
• Sent.: Is the relationship direct or
indirect?
• Sp.: relación directa

23. Indirect Relationship
• Def.: When one variable increases, the
other decreases
• Sent.: Is the relationship direct or
indirect?
• Sp.: relación indirecta

27. Wedge

28. Taper
• Def.: to become smaller or thinner
toward one end. .
• Sent.: A wedge is a device that is thick on
one end and tapers to a thin edge on the
other end
• Sp.: disminución gradua
• What are different things that taper?

29. Wedge
• Def.: a device that is thick on one end and
tapers to a thin edge on the other end.
• Sent.: That force pushes the wedge down
into the wood.
• Sp.: cuña
• With your table make a list of at least 5
different wedges. Raise your hand when
you have your list.

30. Wedge
• Two inclined planes back to back
• How it works: The wedge moves exerting
an output force at a 90° angle
• IMA = length of wedge ÷ width of
wedge

32. Screw

33. Thread
• Def.: a helical groove in a cylindrical
hole ( female thread ), formed by a
tap or lathe tool, or a helical ridge on a
cylindrical bar, rod, shank, etc ( male
thread ), formed by a die or lathe tool
• Kid def.: A twisting raised area around a
cylinder or inside a round hole.

34. Thread
• Sent.: Record the effort force, the
distance lifted and the thread density
for 5 tests
• Sp.: tema
• Discussion: Is a screw with threads closer
together have a higher or lower thread
density?

35. •
Screw
Def.: An inclined plane wrapped around a
cylinder creating spirals called threads.
• Sent.: Like a wedge, a screw is a simple
machine that is related to the inclined
plane.
• Sp.: tornillo
• Discussion: Are there different types of
screws? If so, what are they?

36. Screw
• How it works: Threads increase the
distance over which you exert input
force.
• The output force pulls the screw into the
material. Friction holds it in place.
• IMA = length around the threads ÷ length
of screw

38. Levers

39. Lever
• Def: A rigid bar that is free to pivot
(rotate.)
• Kid Def.: A stiff bar that can rotate freely
• Sent.: What are the advantages of using a
lever to lift this stone?
• Sp.: palanca
• Disc.: What levers do you use every day?

40. Fulcrum
• Def.: The fixed point that a lever pivots
around.
• Sent.: Predict fulcrum placements which
will not be successful.
• Sp.: fulcro
• Disc.: What types of things can be a
fulcrum?

41. 3 Types of Levers

42. 1st Class Lever
• How it works: Changes direction of input
force
• If fulcrum is closer to output force, also
increases force.
• If fulcrum is closer to input force, also
increases distance.
• Calculating IMA:

43. 1st Class Lever
• Ex. paint can opener, scissors

44. 2nd Class Lever
• How it works: Increases force but
doesn’t change direction.
• Calculating IMA:

45. 2nd Class Lever
• Ex.: Wheel barrow, doors, nutcrackers

46. 3rd Class Lever
• How it works: Increases distance but
doesn’t change direction.
• Calculating IMA:

47. 3rd Class Lever
• Ex. Hockey stick, shovel, fishing pole

48. Wheel & Axle

49. Radius
• Def.: a straight line extending from the
center of a circle or sphere to the
circumference or surface
• Sent.: As the radius of the wheel increases,
what happens to its circumference?
• Sp.: radio

50. Regulate
• Def.: To control or direct according to
rule, principle, or law.
• Sent.: The crew's final task at this location
is to construct a device to regulate the
flow of water through the irrigation
canals.
• Sp.: ajustar

51. Wheel & Axle
• Def.: Made of 2 circular/cylindrical
objects fastened together that rotate
around a common axis.
• Object with larger radius is wheel,
and smaller radius is axle.

52. Wheel & Axle
• How it works: Increases your force by
going a longer distance.
• Calculating IMA: IMA = radius of
wheel ÷ radius of axle
• Ex.: door knob, car wheel & axle,
steering wheel, windmill, water wheel

53. Wheel & Axle

54. Pulleys

55. Pulleys
• Def.: A grooved wheel with a rope or
cable wrapped around it.
• Sent.: As the number of supporting ropes
on the pulley increases, what happens to
the length of rope that must be pulled to
lift the stone into place?
• Sp.: polea
• Disc.: What pulleys have you seen?

56. Pulleys
• How it works: Pulling on rope (input
force )causes an object to move up.
• It can decrease the amount of input
force needed and it can change
direction of input force.
• IMA = number of sections of rope
that support object

57. Types of Pulleys
• Fixed –
• How it works: changes
direction of the force
• Def.: Pulley is attached to
an object
• IMA = 1

58. Types of Pulleys
• Movable –
• How it works: decreases
amount of input force
needed, doesn’t change
direction
• Pulley isn’t attached
• IMA = 2

59. Types of Pulleys
• Block and Tackle –
• Def.: made of fixed and
moveable pulleys
• How it works: Decreases
amount of input force
needed
• IMA = 3

60. Compound
Machines
• Def.: A machine that utilizes two or
more simple machines.
• IMA = product of the individual
IMA of each simple machine that
makes up compound machine.

61. Simple Machines in the
Body
• At joints are levers
- muscles are input
force, and output
force does the
work
• Teeth are wedges