Download EM Waves

Nature of
Electromagnetic Waves
Chapter 3.1
Noteworthy Vocab.
 Electromagnetic
 Radiant
Wave
Energy
 Forces & Fields
 Magnetic & Electric Fields
 Atoms
 Protons, Electrons, Neutrons
Wave “Rewind”
Waves transfer Energy without
transferring Matter.
 Mechanical Waves transfer energy by
making particles of matter collide
with one another.
 Ex: Sounds waves, Waves in ocean
 Mechanical Waves can’t travel in
space
 How do you transfer energy through
empty space? Ex - Energy from Sun

Forces & Fields
 Earth
has a force field = Gravitational
Field
 Force is exerted on mass of object.
 Electromagnetic waves is produced by
charged particles in motion.
 Electromagnetic Wave =
Electric field + Magnetic Field
Magnetic Fields

Magnets are surrounded by a magnetic
force field.

Magnets exert magnetic force on other
magnets & magnetic materials.

Magnetic fields cause magnetized
materials to line up along magnetic
lines.
Electric Fields
•
•
•
Atoms contain protons, electrons, &
neutrons.
- Protons & Electrons have electric
charge
Protons => Positive;
Electrons => Negative
A particle with a charge is
surrounded by an electric field.
Electric field exerts a force on other
charged particles.
Making Electromagnetic Waves
 Moving/Vibrating
a charged particle
back and forth causes changing
electric and Magnetic Fields in many
directions.
 Ex:

Electron
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