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Color Addition and Subtraction - Questions

The Color Addition and Subtraction Concept Builder consists of 40 questions organized into 15 Question Groups and spread across three ddifferent activities. The three activities each target a different skill related to color addition and color subtraction. The three activities are described as follows:
 
  • In the Spotlight: Question Groups 1-3 ... To predict the result of adding two primary colors of light.
  • Taking Away: Question Groups 4-9 ... To determine what color(s) is/are absorbed if given the incident light colors and the color appearance.
  • Do the Math: Question Groups 10-15 ... Identify the color equation for a situation involving color addition and subtraction.

Each activity is quite different. While they can be done independently of each other, we think they are scaffolded in a manner such that one builds upon the other. As such, we recommend starting with the first activity and working through them in order. 

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Color Addition and Subtraction

 

Activity 1:  In the Spotlight
Question Group 1
Question 1
A room is darkened. Then two colored spotlights - one RED and one BLUE - shine onto a white screen.  What color will the screen appear at the location where the two spotlights overlap?
 
 
 
 
 
 
 
 
 
 
 
 
 



Question 2
A room is darkened. Then two colored spotlights - one BLUE and one RED - shine onto a white screen.  What color will the screen appear at the location where the two spotlights overlap?
 
 
 
 
 
 
 
 



 
Question Group 2
Question 3
A room is darkened. Then two colored spotlights - one RED and one GREEN - shine onto a white screen.  What color will the screen appear at the location where the two spotlights overlap?
 
 
 
 
 
 
 
 
 
 
 
 
Question 4
A room is darkened. Then two colored spotlights - one GREEN and one RED - shine onto a white screen.  What color will the screen appear at the location where the two spotlights overlap?
 
 
 
 
 
 
 
 
 
 
 
 
 
Question Group 3
Question 5
A room is darkened. Then two colored spotlights - one BLUE and one GREEN - shine onto a white screen.  What color will the screen appear at the location where the two spotlights overlap?
 
 
 
 
 
 
 
 
 
 
 
 
Question 6
A room is darkened. Then two colored spotlights - one GREEN and one BLUE - shine onto a white screen.  What color will the screen appear at the location where the two spotlights overlap?
 
 
 
 
 
 
 
 
 
 
 
 

 
Activity 2: Taking Away
Question Group 4
Question 7
A room is darkened. Three colored spotlights - one RED, one GREEN, and one BLUE - shine on a sheet of paper. A person viewing the paper observes its color appearance to be RED. What color or colors of light are being absorbed by the paper? 
 
 
 
 
 
Question 8
A room is darkened. Three colored spotlights - one RED, one GREEN, and one BLUE - shine on a sheet of paper. A person viewing the paper observes its color appearance to be GREEN. What color or colors of light are being absorbed by the paper? 
 
 
 
 
 
Question 9
A room is darkened. Three colored spotlights - one RED, one GREEN, and one BLUE - shine on a sheet of paper. A person viewing the paper observes its color appearance to be BLUE. What color or colors of light are being absorbed by the paper? 
 
 
 

 
Question Group 5
Question 10
A room is darkened. Three colored spotlights - one RED, one GREEN, and one BLUE - shine on a sheet of paper. A person viewing the paper observes its color appearance to be YELLOW. What color or colors of light are being absorbed by the paper? 
 
 
 
 
 
 
Question 11
A room is darkened. Three colored spotlights - one RED, one GREEN, and one BLUE - shine on a sheet of paper. A person viewing the paper observes its color appearance to be CYAN. What color or colors of light are being absorbed by the paper? 
 
 
 
 
 
 
Question 12
A room is darkened. Three colored spotlights - one RED, one GREEN, and one BLUE - shine on a sheet of paper. A person viewing the paper observes its color appearance to be MAGENTA. What color or colors of light are being absorbed by the paper? 
 
 
 

 
Question Group 6
Question 13
A room is darkened. Two colored spotlights - one RED and one GREEN - shine on a sheet of paper. A person viewing the paper observes its color appearance to be RED. What color or colors of light are being absorbed by the paper? 
 
 
 


 
 
Question 14
A room is darkened. Two colored spotlights - one RED and one GREEN - shine on a sheet of paper. A person viewing the paper observes its color appearance to be GREEN. What color or colors of light are being absorbed by the paper? 
 
 
 

 
 

Question 15
A room is darkened. Two colored spotlights - one RED and one GREEN - shine on a sheet of paper. A person viewing the paper observes its color appearance to be BLACK. What color or colors of light are being absorbed by the paper? 
 
 
 



 
Question Group 7
Question 16
A room is darkened. Two colored spotlights - one RED and one BLUE - shine on a sheet of paper. A person viewing the paper observes its color appearance to be RED. What color or colors of light are being absorbed by the paper? 
 
 
 


 
 
Question 17
A room is darkened. Two colored spotlights - one RED and one BLUE - shine on a sheet of paper. A person viewing the paper observes its color appearance to be BLUE. What color or colors of light are being absorbed by the paper? 
 
 
 


 
 
 
Question 18
A room is darkened. Two colored spotlights - one RED and one BLUE - shine on a sheet of paper. A person viewing the paper observes its color appearance to be BLACK. What color or colors of light are being absorbed by the paper? 
 
 
 



 
Question Group 8
Question 19
A room is darkened. Two colored spotlights - one GREEN and one BLUE - shine on a sheet of paper. A person viewing the paper observes its color appearance to be GREEN. What color or colors of light are being absorbed by the paper? 
 
 
 


 
 
Question 20
A room is darkened. Two colored spotlights - one GREEN and one BLUE - shine on a sheet of paper. A person viewing the paper observes its color appearance to be BLUE. What color or colors of light are being absorbed by the paper? 
 
 
 


 
 
Question 21
A room is darkened. Two colored spotlights - one GREEN and one BLUE - shine on a sheet of paper. A person viewing the paper observes its color appearance to be BLACK. What color or colors of light are being absorbed by the paper? 
 
 
 



 
Question Group 9
Question 22
A room is darkened. Three colored spotlights - one RED, one GREEN, and one BLUE - shine on a sheet of paper. A person viewing the paper observes its color appearance to be BLACK. What color or colors of light are being absorbed by the paper? 
 
 
 
 
 
 
 
 
 
Question 23
A room is darkened. Two colored spotlights - one GREEN and one BLUE - shine on a sheet of paper. A person viewing the paper observes its color appearance to be WHITE. What color or colors of light are being absorbed by the paper? 
 
 
 
 
 


 

 
Activity 3:  Do the Math
 Color equations are symbolic ways of representing the interaction between incident light and the object it shines on. The general form of a color equation is ...
 

 
For the following situation, tap on the buttons to create the corresponding color equation. The equations are expressed in terms of primary colors of light - red, green and blue.
 
 
Question Group 10
Question 24
RED, GREEN, and BLUE spotlights shine on a paper. The paper appears RED to an observer.
 

 






 
Question 25
RED, GREEN, and BLUE spotlights shine on a paper. The paper appears GREEN to an observer.
 

 





 
Question 26
RED, GREEN, and BLUE spotlights shine on a paper. The paper appears BLUE to an observer.
 






 
 
Question Group 11
Question 27
RED, GREEN, and BLUE spotlights shine on a paper. The paper appears YELLOW to an observer.
 

 




 


Question 28
RED, GREEN, and BLUE spotlights shine on a paper. The paper appears MAGENTA to an observer.
 






 
 
Question 29
RED, GREEN, and BLUE spotlights shine on a paper. The paper appears CYAN to an observer.
 




 
 
 

Question Group 12
Question 30
RED and GREEN spotlights shine on a paper. The paper appears RED to an observer.
 





 
 

Question 31
RED and GREEN spotlights shine on a paper. The paper appears GREEN to an observer.
 






 
 
Question 32
RED and GREEN spotlights shine on a paper. The paper appears BLACK to an observer.
 






 
 
Question Group 13
Question 33
RED and BLUE spotlights shine on a paper. The paper appears RED to an observer.
 







 
 
Question 34
RED and BLUE spotlights shine on a paper. The paper appears BLUE to an observer.
 







 
 
Question 35
RED and BLUE spotlights shine on a paper. The paper appears BLACK to an observer.
 





 

 
Question Group 14
Question 36
GREEN and BLUE spotlights shine on a paper. The paper appears GREEN to an observer.
 






 
 
Question 37
GREEN and BLUE spotlights shine on a paper. The paper appears BLUE to an observer.
 






 
 
Question 38
GREEN and BLUE spotlights shine on a paper. The paper appears BLACK to an observer.
 





 
 

 
Question Group 15
Question 39
RED, GREEN, and BLUE spotlights shine on a paper. The paper appears BLACK to an observer.
 







 
 
Question 40
RED, GREEN, and BLUE spotlights shine on a paper. The paper appears WHITE to an observer.