Notes: Conduction, Convection and Radiation

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Name: ___________________________________
Date: ____________________________________
Flynt - _____ Period
_____th Grade Science
Notes: Conduction, Convection and Radiation
When people speak of heat, most of the time they are really talking about thermal energy. Scientists define heat
as the transfer of thermal energy.
Heat is caused by the motion of molecules that make up mater. All molecules are constantly in
motion, but the speed of their motion varies. The ________________ the molecules are
moving, the ________________ the substance is. Heat flows from ________________ objects
to ________________ objects. Coolness is simply the absence of heat. Heat can be transferred
by three principal means: __________________, _________________ and ________________.
Conduction
Conduction is the transfer of energy by _______________ contact. When molecules _______________ or bump
into each other, heat energy is ________________ from faster moving, ________________ temperature particles
to ________________ moving, cooler temperature particles. As they receive heat energy, the slower moving
particles begin to move _______________ and their temperature _______________. They in turn continue to
spread the energy by ____________ with other _________ moving particles and ________ them up.
Heat energy is ________________ from ________ particle to another until ________
the particles in a substance are ________________ at the ________ speed. This process
is known as ________________. Because this process involves a chain reaction with
one particle colliding with the next and so on, the process of ______________ is
sometimes nicknamed the ______________ ______________.
Conduction occurs primarily in ___________ materials that are very _____________,
because the particles are ______________ packed together. An orderly
__________________ of particles also improves thermal conduction. Examples of good conductors include
_______________, _______________, _______________ and _______________. _________________ are
materials that are poor conductors. The particles in these materials are _______________ out and/or very
___________________. Examples of good insulators include _______________, _______________,
_______________, and _______________.
Convection
Heat transfer also occurs in fluids, which include all _______________ and
_______________. _______________ is the transfer of energy due to the
movement of a heated fluid. When a liquid or gas is heated, the molecules move
_____________, they ______________ more often and with greater force, and they
begin to __________ out. This is known as _______________ _______________. If
a fluid is heated from below, the portion of the fluid closest to the heat source will
become less __________ than the fluid above it, which is located farther from the heat source. Due to the force
of gravity, the ______________ dense fluid will begin to __________, which will displace the heated, __________
dense fluid, causing it to rise. The _______________ force is the name given to the upward force caused by
differences in pressure and density within a fluid. If heat continues to be added to the fluid system, the resulting
currents of liquid or gas are called _________________ currents.
What does density mean? _______________________________________________________________________
What is the equation for density?
Radiation
_________________ is the transfer of __________ through the _______________ of space in the form of
________________________ __________, such as visible light and infrared rays.
Conduction, Convection, and Radiation: How do these tie in with the Earth’s Atmosphere?
__________________
_________________________
Sunlight travels through the
vacuum of space and warms the
ground when absorbed.
Warm, less dense air rises. Cold, more dense air sinks.
__________________________
The warm ground heats the air just above the surface by direct contact.
Word Bank
air
all
arrangement
buoyant
closely
collide
collide
colliding
conduction
conduction
conduction
conduction
convection
convection
convection
convection
cooler
copper
dense
dense
diamond
direct
disorganized
domino effect
electromagnetic waves
energy
energy
faster
faster
faster
gasses
gold
hotter
Insulators
iron
less
liquids
more
one
quartz
radiation
radiation
radiation
rises
rubber
same
sink
slow-
slower
solid
speed
spread
spread
thermal expansion
transferred
transferred
vacuum
vibrating
warmer
warmer
wood
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