Simple Machines

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Simple Machines
• First, rank the following words from 0-5 (0=
you have never heard of this word & 5= you
know the word VERY well). Second, explain
what the following terms mean in your own
words:
– Machine
– Simple machines
– Work
– Force
– Work input/Work output
– Lever
-Pulley
-Wheel & axle
-Inclined plane
-Wedge
-Screws
-Compound machine
YOURS:
TEXTBOOK:
• A machine is a device
that makes work easier
by changing the size or
direction of a force.
• Examples: wheelchair,
scissors, chopsticks
YOURS:
TEXTBOOK:
• A machine or simple
device without
moving parts.
• Examples: lever,
pulley, wheel & axle,
inclined plane,
wedge, screw
YOURS:
TEXTBOOK:
•
•
•
Work is the transfer of energy
to an object by using a force
that causes the object to
move in the direction of the
force.
Work is done on an object if
two things happen: 1) the
object moves as a force is
applied, 2) the direction of the
object’s motion is the same
as the direction of the force.
Examples: pushing a ball up
a hill
YES OR NO
YES
OR
NO
YOURS:
TEXTBOOK:
• A push or a pull
exerted on an object
in order to change
the motion of the
object; force has
size and direction.
• Examples: people,
bulldozer, static
electricity
YOURS:
TEXTBOOK:
• Work input is the
work done on the
machine.
• Work out put is the
work done by the
machine.
• Examples: opening
a paint can
The Six Simple Machines
The Six Simple Machines
YOURS:
TEXTBOOK:
• A lever is a simple machine
that has a bar that pivots at
a fixed point, called a
fulcrum.
• Examples: first-class lever
(see saw), second-class
lever (wheelbarrow or soda
bottle opener), third-class
lever (lifting weights or
hammering a nail)
The Six Simple Machines
Lever
First-Class Lever
Second-Class Lever
Third-Class Lever
Elementary School
Middle School
High School
First-Class Lever
1st classfulcrum is
placed between
the load and the
force
Elementary School
Second-Class Lever
2nd class- the
load is between
the fulcrum and
the force
Middle School
Third-Class Lever
3rd class- the
force is between
the load and the
fulcrum
High School
YOURS:
TEXTBOOK:
• A simple machine
that has a grooved
wheel that holds a
rope or a cable.
• Examples: fixed,
moveable, block and
tackle
The Six Simple Machines
Lever
Pulley
Types of Pulleys:
YOURS:
TEXTBOOK:
• A simple machine
consisting of two
circular objects of
different sizes.
• Examples: car’s
wheel & axle, faucet
The Six Simple Machines
Lever
Pulley
Wheel & Axel
YOURS:
TEXTBOOK:
• A simple machine
that is a straight,
slanted surface; a
ramp.
• Examples: ramp or
slide
The Six Simple Machines
Lever
Inclined Plane
Pulley
Wheel & Axel
YOURS:
TEXTBOOK:
• A simple machine
that is made up of
two inclined planes
that move; often
used for cutting.
• Examples: knife,
axe, door stop
The Six Simple Machines
Lever
Pulley
Inclined Plane
Wedge
Wheel & Axel
YOURS:
TEXTBOOK:
• A simple machine
that consists of an
inclined plane
wrapped around a
cylinder.
• Examples: screw,
light bulb
The Six Simple Machines
Lever
Pulley
Wheel & Axel
Inclined Plane
Wedge
Screw
YOURS:
TEXTBOOK:
• A machine made up
of more than one
simple machine.
• Examples: manual
can opener
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