When light hits an object you can't see through, such as an apple, it can reflect, or bounce off, of it. When light hits a more transparent object, such a window, it transmits, or goes through, it.
Watch this animation to find out how reflected light and a special case of transmitted light called refraction affect how we see objects.
As you watch the segment, you might want to check the definitions of specific terms. In addition to the glossary words listed above, the terms wavelength and absorb will be described.
Stop the animation at any time, watch it again, or read the transcript.
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Take a look. What you are seeing is not exactly that apple. What you are seeing is light energy interacting with the apple, being detected by your eye and interpreted by your brain. Different objects have different properties that absorb, reflect and even allow light energy to pass through.
But not all wavelengths of energy do the same thing in every given object or medium.
This red apple absorbs all visible wavelengths of light energy except the red. The result? Red wavelengths are reflected to our eye and the apple looks red to us.
A green apple looks green because it reflects the green wavelengths.
Some matter allows light energy to go through it (a glass of water) and as it does, the energy interacts with the matter and its speed and trajectory change depending on the angle it hits. This is called refraction. The result? That cool broken-straw illusion, why you are no good at spearfishing, and best of all, the lens on your eyeball that allows you to see.
Write a sentence describing each of the following terms:
1) Reflect
2) Refract
3) Absorb