Color - Our Perception of the EM Spectrum

What do you know about color?

In this section you are asked some questions to get you thinking about color. You are only graded on putting forth an effort to answer the questions in this section. The purpose of this is to compare what you know before and after going through the activity.

1. How many primary colors of light are there, and what are they?

2. Why are there that many primary colors?

3. What do you get when you mix all colors of light together?

4. What color would blue socks appear under red light?

Activity 1 - Color Mixing

This activity can be done one of two ways:

• Using the three different primary color lights and shining them on to a white surface. LED lights work the best because they are monochromatic (single wavelength)
• Using the custom color function on this Google Document. When you go to define a custom color, you can choose them, but you can also put in the code. Here is how the code works:

• The code takes the form # _ _ _ _ _ _
• The six digits (blanks) encode for the relative strength of each of the primary colors. The strengths range from 00 (off all the way) to ff (on all the way). ff means 256 in base 16.
• hit edit on the drawing to do the color addition.

Activity 2 - The Subtractive Colors

Using what you have learned about the subtractive colors fill in the color wheel below. Remember, when mixing, subtract all necessary colors off of white and see what you have left!

Activity 3 - Under a New Light

Using what you know about color, try to predict what will happen in each of the scenarios below. The top row represents what color of paper you are shining the light on and the sidebar illustrates what color light you are shining.

Now go back and observe what happens in each condition.

Activity 4 - Color Math

Write an equation that would illustrate the result of each of the following situations:

1. A red light shining on a blue pigmented sock.

2. A cyan light shining on a yellow pigmented banana.

3. A blue light shining on a magenta pigmented cartoon dog.

Activity 5 - Other Causes of Color

Research one of the other causes of color, and describe it in a paragraph here.

Visit the Causes of Color website for some inspiration.