Newton and the prism. Apologia Physical Science Mod. 10.

Isaac Newton was a brilliant scientist that is without question.  He was also a brilliant inventor.  You can read my last post about Newton here.  One of Newton's many inventions is the glass prism.  Newton understood light in a different way than anyone else, and it is with thanks to him that scientist today now have a better understanding of light.

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Did you know in order to have white light, all the colors of the rainbow have to combine to do so? What?  Seems strange but it is true.  Newton understood this concept and created a glass prism to prove just that.  He could combine the colors of the rainbow and form white light.  You see, when light passes through a prism, the colors that make up the white light get separated out.  The reason for this is that each color has its own wavelength and each of those wavelengths bend to a different angle.

How is that possible?  Let's review what light actually is and is not first.

Light is not matter, and it has no mass.  Light is unique as it behaves both as a wave and a particle.

Scientist believe light is a form of energy made from photons (bundle of electromagnetic energy).

Light will behave in different ways depending on the type of matter it comes in to contact with, for example, light will pass right through some types of matter such as water or air.

This is known as transparent matter.

Some matter such as a desk or a horse reflect light, and this is called opaque matter.  When an object has both of the other two properties, it tends to scatter the light which is known as translucent matter.

More facts:

We all need light to survive especially sunlight which provides warmth, vitamin D, a source of energy, and photosynthesis.

In terms of physics, the term electromagnetic radiation is known to us as simply light.  Speaking in general terms, the human eye cannot see the entire electromagnetic spectrum.  For example, ultraviolet light and infrared light cannot be seen by the human eye.

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Did you know that some animals can see parts of the electromagnetic spectrum that humans cannot? There are many larger insects that can actually see ultraviolet light.

Did you know that light moves at the fastest recorded speed in the universe?   That speed is 186,282 miles per second to be exact.

It takes light about 1.255 seconds to reach from earth to the moon.

Sunlight can reach depths of 262 feet in the ocean.

So that is a wrap on the prism.  All the colors of the rainbow align to form white light in a very specific matter.

Visit NASA for a great lesson plan grades 9-12.
Experiment to try.
Activities for the younger kids.
Here is a quiz on light.