Answer to Question #212196 in Electricity and Magnetism for Krynt

Question

Enrichment Activity 2. Beam Me a Light

In this activity you will be needing:

Flashlight

Red, blue, and green construction paper

See-through colored cellophane

Masking tape or a rubber band

Research Questions

1. Why did the papers look white, red, blue, and green (respectively) in white light?

2. How did the construction and cellophane affect the white flashlight beam?

3. Why did the yellow and green papers seem to lose their color when red light was

shined on them?

Procedure

1. Darken the room as much as possible.

2. Turn on the flashlight and aim it at the white paper. Observe and record the

color of the paper in the data table,​

Question:

1. Why did papers look white, red, blue, and green (respectively) in white light?

2. How did the construction and cellophane affect the white flashlight beam?

3. Why did the yellow and green papers seem to lose their color when red light is shined on them?

Answer 1

1. When white light is shining on papers, then red, green and blue light is shining on the papers. When the paper absorbs blue light, green and red light will bounce off from the paper. Red and green light reaching your eye gives the appearance of yellow; therefore, because of this the paper will appear yellow.

2. Cellophane is transparent since light pass through it and you can see through them. However, the color of light seen changes. Thus if you look through red cellophane, the other side appears shades of red and if you look through green cellophane, everything appears green.

3. When red and green light shine on a paper it appears yellow, since Yellow light is a combination of red and green light. In order to reflect red and green light, these two primary colors of light must be present in the incident light.