gcsescience.com                                             39                                             gcsescience.com

Waves

Electromagnetic Waves - General.

Electromagnetic waves are transverse waves
which have both an electric and a magnetic effect.
Electromagnetic waves are sometimes called rays or radiation
(these words are also used for radioactivity).

All electromagnetic waves travel at the same speed (in a vacuum).
Electromagnetic waves travel very quickly.
There is nothing which can travel faster.
Their speed is 300,000,000 m/s in a vacuum
(that is 300 million metres per second - not easy to imagine!).

They can have a wide variety of wavelengths and frequencies
which form the electromagnetic spectrum.

Electromagnetic waves are unusual because they
do not need any substance to get from one place to another.
They can travel through a vacuum.
Light and infra-red radiation (heat) can reach the Earth from the Sun
through the vacuum of space.

back      Headings      Waves      Search      Questions      next

gcsescience.com              Contents             Index              Quizzes             gcsescience.com

Copyright © 2008 Dr. Colin France. All Rights Reserved.