An electromagnetic wave transfers energy through a field and forms when atomic particles become electrically charged. EM waves come in a spectrum and most that reach Earth come from the Sun. They travel at 186,000 miles per second in a vacuum, also known as the speed of light. Gamma rays are most harmful but can treat diseases while transparent materials allow light to pass through and opaque materials block it.

1. An ELECTROMAGNETIC
WAVE is a disturbance
The range of all EM
that transfers energy
frequencies is known as the
through a field.
electromagnetic spectrum.
EM waves form when The Electromagnetic Spectrum-
atomic particles become longest to shortest
electrically charged. • Radio Waves
• Microwaves
Most EM waves that are in
the Earth ' s environment • Infrared Light
come from the SUN .
• Visible Light
• Ultraviolet Light
Radiation is the transfer of
energy in the form of EM • X-Rays
waves. • Gamma Rays
EM waves travel 186,000 Gamma Rays are the most harmful to
mi/second in a vacuum. humans, but can be used to treat
diseases, including cancer.
The constant speed of EM waves in a
vacuum is also known as The Speed of Absorption is the
Light. disappearance of an EM
wave into the medium .

2. Transparent materials
allow most of the
light that strike them
to pass through.
The colors that make up visible light
are:
Translucent materials
transmit some of the light, • RED
but also causes some light • ORANGE
to spread out in all
• YELLOW
directions.
• GREEN
• BLUE
Opaque materials do not allow any
light to pass through them because • INDIGO
they reflect and/or absorb light.
• VIOLET
Polarization is a way of filtering
light so that all of its waves The production of light by
vibrate in the same direction.
material at high temperatures is
called incandescence.
Fluorescence is when light
occurs when a material absorbs
Bioluminescence is the
EM radiation of one wavelength
and gives off EM radiation of a production of light by living
different wavelength. organisms.