Honors Physics - Chapter 16: Labs

Chapter 16: Color Laboratory Investigations

What Does A Prism Do?

Color Addition

Color Subtraction

Colored Objects

Chapter 16: Laboratory Investigations

There are four mini-laboratory investigations in chapter 16. Look though each lab and make observations and conclusions using the pictures given, then answer the questions for each lab on the color lab laboratory investigation found in google classroom.

Laboratory Equipment for All Labs

This Light Box and Optical Set makes it easy to perform experiments involving the optics of lenses, mirrors, and prisms, as well as providing a versatile way to display primary and secondary colors; and both additive and subtractive color mixing. The double-ended light box contains a halogen lamp powered by a wall-mount AC adapter and cooled by a built-in fan. One end carries a cylindrical lens and slots for mounting the three slit diaphragms for ray optics. The other end carries two adjustable mirrors and an open area for color mixing and subtraction.

This set comes with an assortment of lenses, prisms, acrylic blocks, mirrors, slit plates, color filters, and color paddles that we will be using for laboratory investigations in chapters 16, 17, and 18.

The adjustable mirror side is only used for the color addition lab.

Lab: What does a Prism Do?

Objective:

To learn how a prism splits white light into its component colors.
To become familiar with the white light spectrum.

Procedure:

The power supply has been plugged in and we are using the end of the light box without the swinging doors. The wide slit mask was inserted into the slot nearest the light bulb. After the power supply was turned on a beam of light is projected through the slit. The equilateral prism was arranged as shown in the picture. What do you observe in the picture?

2. A dot was placed on the paper in the middle of the red light (R), green light (G), and blue light (B.) Look at the pictures and observe what happens when a red filter is placed in the outer slot of the light box, a green filter, and a blue filter. Make a general statement about your observations about the filter and the light coming out of the prism.

Red Light

Green Light

Blue Light

Lab: Color Addition

Objective:

To learn the primary additive colors and how they add.
To learn the complementary colors.

Procedure and Observations:

The power supply has been plugged in and we are using the end of the light box with the swinging doors. Insert the red, green, and blue filters in the slots at the end of the light box, one on each side. You can turn off a side light by closing the door, and you can turn off the front light by inserting a mask. Turn on the power supply. Beams of colored light should be projected from the light box. Project the colors two at a time on the screen. Refer to the picture on the website. Record the color that you see where they overlap.

Red + Green

Green + Blue

Red + Blue

2. Now add all three lights and record the color that forms where they all overlap.

Red + Green + Blue

3. Now add the following combination and record the color that forms.

Blue + Yellow

Red + Cyan

Green + Magenta

Lab: Color Subtraction

Objective:

To learn the subtractive colors and how they subtract.

Procedure and Observations:

The power supply has been plugged in and we are using the end of the light box without the swinging doors. Filters were placed into the slots. Refer to the pictures below to see the colors of the filters and observe what light is transmitted.

Procedures and Observations #1-3

Yellow Filter

Magenta Filter

Cyan Filter

Procedures and Observations #4-7

Yellow and Cyan

Yellow and Magenta

Cyan and Magenta

Magenta, Yellow, and Cyan

Lab: Colored Objects

Objective:

To learn how colored objects appear in different colors of light.
To learn how color printing is done.

Procedure and Observations:

The power supply has been plugged in and we are using the end of the light box without the swinging doors. Filters were placed into the slots and different colored objects were placed in front of the filters.
1. For example, when you hold the red colored card in the red colored light. It should appear bright because red objects reflect red light. You would record this in the table on your laboratory investigation by writing "YES in the square for the red light and a red object.
2. When you hold the blue colored card in the red light, it should appear dark because blue objects absorb red light and do not reflect it. You would record this in the table on your laboratory investigation by writing "NO" in the square for red light and blue object.
Refer to the pictures of various colored objects below in the different light to fill in your table.

Objects in Red Light

Red Object

Blue Object

Green Object

Yellow Object

Magenta Object

Cyan Object

Objects in Blue Light

Red Object

Blue Object

Green Object

Yellow Object

Magenta Object

Cyan Object

Objects in Green Light

Red Object

Blue Object

Green Object

Yellow Object

Magenta Object

Cyan Object

Procedure and Observations:

3. The yellow color filter was placed in the slot in the light box. The red colored object was held in the yellow light. Record what color you see in the pictures of various colored objects below in the different light to fill in your table. If an object appears to be dark, then write "BLACK" in the table.