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Waves

Light - General.

Light is a transverse wave.
It is one part (region) of the electromagnetic spectrum.
Light is the visible region, it is the part used by our eyes to see.
Like any electromagnetic wave, light can travel through a vacuum.
Light travels through the vacuum of space from the Sun to the Earth.

Light travels very quickly. There is nothing which can travel faster.
The speed of light is 300,000,000 m/s in air
(that is 300 million metres per second - not easy to imagine!).
The speed of sound in air is approximately 330 m/s,
so light is almost one million times as fast.

You can sometimes notice that light is travelling faster than sound.
In a storm, the light and the sound are generated
at the same time but you see the lightning flash
before you hear the sound.
The light has travelled to your eyes
more quickly than the sound has travelled to your ears.

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