Fun Friday – Exploring Light!

What is light?

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 Light is a type of energy called “Electromagnetic” (EM) radiation. When we see light we see it in straight lines called rays.

The scientific study of light is called Optics. All Electromagnetic energy (including light) actually travels in waves.  Light is the only type of EM energy that we can see (this is called the visible spectrum).  Other types of EM radiation include radio waves, microwaves and (Ultra Violet) UV waves.



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Did you know… some animals can see light that is not visible to humans?  Bees, for example, can see UV light.  This allows them to follow UV patterns on many flowers which lead them to the source of nectar.

 

The colour of light

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Light travels in waves; the wavelength of light determines its colour.  Light with the longest wavelength is red; light with the shortest wavelength is violet. Sunlight appears as white light but it is actually made up of all the colours of the rainbow. Sunlight can be split into all of its different colours and that is how a rainbow is made.
Did you know… the brightness of light is measured in lumens? Our eyes are usually comfortable with a brightness up to 3,500 lumens.


How is a shadow made?

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When light rays hit an object they bounce (reflect) off it.  This is how shadows are made, they are the dark patches behind an object that light cannot get through.
Did you know… the biggest shadow we will ever see is a solar eclipse?

How fast does light travel?

The speed of light is 300,000 kilometres (or 186,000 miles) per second. Distance in space is measured in light years; it is the distance that a ray of light travels in one year – 9.46 trillion kilometres (5.8 trillion miles).

Did you know… it

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