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Force and Motion
STARS Teacher Workshop
Sunshine State Standards
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Force and Motion
Standard SC.C.2.2.1
Recognizes that forces of gravity, magnetism,
and electricity operate simple machines.
We well review gravity, magnetism and
electricity, and complete a number of
activities that demonstrate how they can
operate a simple machine.
What is a simple machine?
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What is Simple Machine?
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A device for overcoming resistance at one point by applying
force at some other point
A simple device, such as a lever, pulley, or inclined plane; a
machine without moving parts
Examples of Simple Machines
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Lever
Inclided Plane
Wedge
Pulley
Wheel and Axle
Screw
The Three Simple Machines
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The Lever
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The Inclined Plane
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A simple machine consisting of a rigid bar
pivoted on a fixed point and used to transmit
force, as in raising or moving a weight at one
end by pushing down on the other.
The inclined plane is a kind of simple
machine with slanted surface.
The Pulley
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The pulley is a simple machine made of a
rope or chain wrapped around the wheel.
Other Machines Simple
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The Wedge
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The Wheel and Axle
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A simple machine consisting of The wedge is
two inclined planes joined back to back.
The wheel and axle is a simple machine
made of a large wheel attached to a post or
axle.
The Screw
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The screw is an inclined plane wrapped
around a post.
Gravity and Simple Machines
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What is Gravity?
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Gravity is a Force which pulls objects
downward toward the earth.
A pulley can be used to make work seem
easier by change the direction of force to
work with gravity rather than against it
Gravity
The Lever
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Activity
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We will use the principles governing a lever to
calculate how much weight is needed to balance
the level on the fulcrum.
Magnetism Electricity and Simple Machines
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What is Magnetism
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What is Electricity?
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a class of physical phenomena that include the attraction for iron
observed in lodestone and a magnet, are inseparably associated
with moving electricity, are exhibited by both magnets and electric
currents, and are characterized by fields of force
The physical phenomena arising from the behavior of electrons
and protons that is caused by the attraction of particles with
opposite charges and the repulsion of particles with the same
charge.
How can electricity be used with simple
machines?
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Magnetism and Electricity come together to create a
motor which can be used with simple machines.
Simple Machines and Motors
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The Screw
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Screw are often twisted into wood or metal
surfaces using drill
Wheel and Axle
The Pulley
The Motor
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What is a motor?
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A device that converts any form of energy into
mechanical energy, especially an arrangement of
coils and magnets that converts electric current into
mechanical power.
In most DC electric motors, the rotor is an
electromagnet that turns within a shell of stationary
permanent magnets. The rotor will spin as long as
this current reverses each time its magnetic poles
reach the opposite poles of the stationary magnets.
The most common way to produce these reversals
is with a commutator. A simpler commutator
has two curved plates that are fixed to the rotor
and connected to opposite ends of the wire coil.
The Motor
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Hand on Activity
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The Human Motor
DC Motor Applet
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http://www.sciencejoywagon.com/physicszone/lesson/other
pub/wfendt/electricmotor.htm
The Motor (Activity)
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Building a motor
References
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Proteacher
 http://www.proteacher.com
Enchanted Learning
 http://www.enchantedlearning.com/physics/machines/Lev
ers.shtml
Physical Science
 http://www.sirinet.net/~jgjohnso/simple.html
Dirtmeister
 http://teacher.scholastic.com/dirtrep/simple/pulley.htm
UBC Let’s Talk Science Partnership Program
 http://www.gss.ubc.ca/LTS/electromagnetic_motors.html