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Science starter
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The temperature inside Mrs. McMullan’s house is
20ºC, but it is snowing outside and the
temperature is below 0ºC. Mrs. McMullan is able
to stay warm in her house, because she has
transformed electrical energy to ____ energy.
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kinetic
thermal
chemical
mechanical
Science starter
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What is the purpose of simple machines?
– to reduce the distance that an object needs to
be moved
– to reduce the force needed to move an object
over a distance
– to reduce the mass of an object that needs to be
moved over a distance
– to reduce the amount of work needed to move
an object over a distance
Science starter
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If an object is too heavy to move up a ramp,
what is the best way to fix the problem?
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increase the slope of the ramp
increase the length of the ramp
increase the friction of the ramp
increase the elevation of the ramp
Science starter
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What are the properties of magnetism?
What is the purpose of an electromagnet?
What is magnetism?
Science starter
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How is the relationship between electricity
and magnetism different in generators from
electromagnets?
agenda
• Science Starter
• Standard/objective/eq
• Review: Relationship of magnetism &
electricity
• Review: spinning coil motor lab
• Magnetism & electricity notes
Magnetism & electricity
6-5.3
What is magnetism?
• Force that attracts or repels magnetic metals
• Magnetic Field=applies the force without
touching magnetic metals
What are the properties of magnetism?
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Poles (North & South)
Attract (opposite poles, iron & steel)
Repel (same poles)
Strength of Magnetic Field (strongest @ poles)
How are magnetism & electricity related?
• They work together to form magnetism:
– Wrap wire around iron core & connect wire to
source of electricity
• They work together to form electric currents:
– Coil of wire spinning around magnet
– Magnet spinning around coil of wire
What machines use magnetism & electricity
together?
• Simple Electric Motors
• Electromagnets
• Generators
Machines that use magnetism & electricity
6-5.3
electromagnet
Coil of wire
• How to Create:
o Wrap coils of wire
around iron core
o Connect wire to source
of energy
• Purpose: to make a
magnetic field
• When wire is
Iron core
disconnected from
power source,
electromagnet doesn’t
work
Source of
electricity
generator
• Purpose: produce
electric currents
• How to Create:
– Wrap wire around iron
core
– Rotate core near a
magnet OR rotate a
magnet near core
• Energy Transformation:
mechanical  electrical
generator
generator
• Produce electrical
energy for homes
• Coils of wire are
stationary
• Magnets are rotated by
turbines (huge wheels
pushed by water, wind,
or steam)
Simple electric motor
• How to Create:
magnet
electromagnet
o Make an electromagnet
o Rotate electromagnet
between poles of a
magnet
• Energy Transformation:
electrical  mechanical
• Like poles repel (push)
electromagnet,
opposite poles attract
(pull) electromagnet
• This creates rotation of
motor
magnet