I have tried this experiment. Why is it that the light that fills in the shadow, let's say for example the red and blue light filling in where the green light is blocked, is a much more intense magenta color than the red and blue lights alone shining on the white board making it a (much less intense) magenta color?

Name: What's going on: Light travels in straight lines
Uploaded: 2014-11-12T03:23:05Z
Description: What's the science behind the phenomenon of colored shadows? Light travels in straight lines, but we have three different-colored bulbs spaced several inches apart.

I understand that by "a much more intense magenta color" you understand your perception and not an actual measurement. It's because of the contrast. When the whole space is one color your eyes and brain get used to it and don't perceive it as as intense.

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Course: Exploratorium > Unit 2

Lesson 5: Colored Shadows

What's going on: Light travels in straight lines

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What's the science behind the phenomenon of colored shadows? Light travels in straight lines, but we have three different-colored bulbs spaced several inches apart. Created by Exploratorium.

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shozab.zaidi96
Posted 9 years ago. Direct link to shozab.zaidi96's post “A fish in the glass bowls...”
A fish in the glass bowls sometimes looks where its position is not actually whats the reason it is in wrong position it is in same position but when we look from top it converts the position virtually
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shozab.zaidi96
Posted 9 years ago. Direct link to shozab.zaidi96's post “when light is traveling a...”
when light is traveling and stops on the point what the point is called what will be the distance of image from the object
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(3 votes)
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Jeanie Shanks
Posted 9 years ago. Direct link to Jeanie Shanks's post “I have tried this experim...”
I have tried this experiment. Why is it that the light that fills in the shadow, let's say for example the red and blue light filling in where the green light is blocked, is a much more intense magenta color than the red and blue lights alone shining on the white board making it a (much less intense) magenta color?
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(2 votes)
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- Hyta
  Posted 8 years ago. Direct link to Hyta's post “I understand that by "a m...”
  I understand that by "a much more intense magenta color" you understand your perception and not an actual measurement. It's because of the contrast. When the whole space is one color your eyes and brain get used to it and don't perceive it as as intense.
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  (2 votes)
Anush Somasundaram
Posted 8 years ago. Direct link to Anush Somasundaram's post “so the shadow of the red ...”
so the shadow of the red light is filled in by the blue right if I'm correct.
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(1 vote)
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shozab.zaidi96
Posted 9 years ago. Direct link to shozab.zaidi96's post “light can also travel in ...”
light can also travel in curved ways why it always travels in straight line?
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- Max_Smax
  Posted 8 years ago. Direct link to Max_Smax's post “light travels in a straig...”
  light travels in a straight line from its source but it can bend around objects. I outer space they found that some objects were a long distance away from where they thought they were because the light was bent around other celestial bodies.
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lilalicia
Posted 5 years ago. Direct link to lilalicia's post “How fast does light trave...”
How fast does light travel
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Video transcript

- The important concept to understand the colored shadows is that light travels in straight lines. I'm gonna show that using this ruler. I'm gonna put the one end of the ruler at the center of the red bulb. It shows the light traveling along one path to the screen. Of course, light from the red bulb hits everywhere on the screen traveling in straight lines, however along this path, if I put the pencil there, the pencil blocks the light traveling in a straight line along the ruler, and makes a shadow on the wall. However, light from the blue bulb also travels in straight lines, and its straight line misses the pencil, and fills in the shadow from the red light.