electromagnetic energy. energy is the ability to do work. electromagnetic energy is the energy...
TRANSCRIPT
Electromagnetic Energy
Energy is the ability to do work.
Electromagnetic energy is the energy radiated by all matter in the universe
that is not at absolute zero.
Absolute zero is the temperature at which
particles of matter (atoms) exhibit no motion
(-273°C or 0 Kelvin).
Electromagnetic energy moves in the form of transverse waves. A
transverse wave vibrates 90° to the direction in
which the wave is moving.
Electromagnetic Energy
A wavelength is the distance between any two corresponding
points (crest or trough) on a cycle.
crest
trough
Types of Electromagnetic Energy
Types of electromagnetic energy are determined
by their wavelength
Visible light is the only form of electromagnetic energy that can be seen.
Wavelengths shorter than visible light are known as
short–wave electromagnetic energy.
Wavelengths longer than visible light are known as
long–wave electromagnetic energy.
Electromagnetic SpectrumRT =
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Interactions Between Electromagnetic Energy and the Environment
REFRACTION: waves bend as they pass through a material
REFLECTION: waves bounce off material
SCATTERED: waves refracted and/or reflected in many directions as they pass through a material
TRANSMITTED: waves pass through a material
ABSORPTION: waves taken into a material
Energy Absorption vs. Surface Properties
The characteristics of a surface can determine how
much electromagnetic
energy is absorbed.
Dark surfaces tend to absorb more electromagnetic energy than light
surfaces.
Light surfaces tend to reflect electromagnetic energy.
Rough surfaces tend to absorb more
electromagnetic energy than smooth surfaces.
Rough surfaces have a greater surface area for electromagnetic energy
to be absorbed by.
Energy Absorption vs. Surface Properties
Surfaces that are good absorbers of
electromagnetic energy tend to be good radiators of
electromagnetic energy.
-- Dark clothes will absorb more electromagnetic energy and radiate
more energy.
-- The boy will heat up more quickly.
-- Light colored clothing will reflect
most electromagnetic
energy.
-- Not much energy to be
radiated.
-- The boy will not heat up as quickly.