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Course: Exploratorium > Unit 2
Lesson 5: Colored Shadows- Colored shadows: Introduction
- Build your own colored shadows: Materials & steps
- What's going on: Light travels in straight lines
- What’s going on: Human color perception
- Yellow and cyan challenge
- Yellow and cyan solution
- Further explorations with colored shadows
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What's going on: Light travels in straight lines
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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- 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(6 votes)
- when light is traveling and stops on the point what the point is called what will be the distance of image from the object(3 votes)
- 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?(2 votes)
- 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.(2 votes)
- so the shadow of the red light is filled in by the blue right if I'm correct.(1 vote)
- light can also travel in curved ways why it always travels in straight line?(1 vote)
- 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.(1 vote)
- How fast does light travel(1 vote)
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.