## Light and Color Notebook Labs

The following items should be in the Light and Color portion of your notebook. They should be clearly organized and easy to find. Use an organizational system and label all work. Each lab will be graded separately.

### L1. Ripple Tank Lab

Question:
How is the path difference related to the wavelength of light for a two-point source interference pattern?

Purpose:
To develop two equations (one for nodes and one for anti-nodes) for relating the path difference to the wavelength for a two-point source interference pattern.

A complete lab write-up includes a Title, a Purpose, a Data section, a Conclusion and a Discussion of Results. The Data Section should include the provided pattern with marked nodal and antinodal lines, marked nodes and antinodes, and a table of data listing S1P, S2P and PD distances expressed in terms of wavelengths. The Conclusion should state two equations relating path difference to wavelength - one for nodal positions and the other for antinodal positions. The symbols used in the equation should be defined. The Discussion of Results section should describe the evidence which leads to the conclusion statement; specific trials of data should be referenced in order to demonstrate the evidence leading to the equation.

### L2. Two-Point Source Analysis Lab

Question:
What are the limitations of the two methods of calculating the wavelength of light from an interference pattern?

Purpose:
To analyze a two-point source interference pattern using both the path difference equation and Young's equation and to compare the effectiveness of each equation in determining the wavelength.

A complete lab write-up includes a Title, a Purpose, a Data section, and a Conclusion/Discussion. The Data section should include the provided diagram and data table; work should be clearly shown and labeled for the couple of calculations which are performed. The Conclusion/Discussion should include a description of your results and a comparison of the calculated wavelengths with the measured wavelength. Comments should be made about which method (equation) is most effective; the evidence for your comments should be discussed.

### L3. Young's Experiment Lab

Question:
What is the wavelength of red laser light?

Purpose:
To determine the wavelength of red laser light in units of nanometers.

A complete lab write-up includes a Title, a Purpose, a Data section, a Conclusion and a Discussion of Results. The Data section should include a top view of the experimental set-up with measured values labeled on the diagram; the measurements should be related to the variables y, d, m, and L and the units should be clearly stated. Calculations should be clearly and systematically shown; conversion of units should be part of the work; units should be stated. The Conclusion should state the experimentally-determined value for the wavelength of red light. The Discussion of Results section should include an error analysis; a percent error calculation should be included in the discussion; work should be shown.

### L4. Getting it Right With Light Lab

Question:
What model of light and of Polaroid filters would provide a suitable explanation of how they work?

Purpose:
To explore Polaroid filters and to develop and describe a model which explains how they work.

A complete lab write-up includes a Title, a Purpose, a Data section, and a Conclusion/Discussion of Results. The Data section should include a documented record of the tests which were performed with the filters and the corresponding observations and results. The record should be clear and accentuated by diagrams and sketches. The Conclusion/Discussion should present a logical model of filter construction and light behavior and should utilize the model to explain how the filters and the set of filters serve to filter light. The discussion should be supported by specific references to evidence which was documented in the Data section.

### L5. Diluted by Distance Lab

Question:
What is the mathematical equation relating the illuminance on a surface and the distance between the surface and the source?

Purpose:
To determine the mathematical equation relating the illuminance (E) on a surface and the distance (d) the surface is from a light source.

A complete lab write-up includes a Title, a Purpose, a Data section, a Conclusion and a Discussion of Results. The Data section and Conclusion section are similar to other labs performed this year; review the Wait! Hmmm. Gee. Lab (Newton's Laws Unit), F-m-a Lab (Newton's Laws Unit), Ut Tensio, Sic Vis Lab (Newton's Laws Unit), It's a Breeze Lab (Vectors and Forces Unit), Modified Atwood's Machine Lab (Vectors and Forces Unit), Stopping Distance Lab (Energy Unit), How Much? Lab (Refraction Unit), The Lens Equation Lab (Refraction Unit), and the Period of a Pendulum Lab (Waves Unit). The Discussion of Results section should include a discussion of how the experimentally-derived equation was developed. It should be compared to a theoretical equation found in a textbook or online site.

Question:
What is the result of adding combinations of the three primary colors of light in equal and unequal intensities?

Purpose:
To determine the result of adding primary colors of light in equal and unequal intensities and to develop four general rules of color addition for adding light colors in equal intensity.

A complete lab write-up includes a Title, a Purpose, a Data section, and a Conclusion/Discussion of Results. The Data section should include the provided table with all rows completed. The Conclusion/Discussion should respond to the question raised in the Purpose of the lab.

### L7. Taking Away from RGB Lab

Question:
What is the result of mixing primary pigment colors and what strategy could be used for predicting such results?

Purpose:
To observe the result of mixing primary pigment colors and to summarize the results using seven color subtraction principles.

A complete lab write-up includes a Title, a Purpose, a Data section, a Conclusion/Discussion. The Data section should include labeled color diagrams with actual colored markers being used to add the primary pigments. The Conclusion/Discussion should describe the seven possibilities and explain what each pigment or combination of pigments subtracts from RGB light.

### L8. Painting with CMY Lab

Question:
What is the result of mixing primary pigment colors and what strategy could be used for predicting such results?

Purpose:
To predict the primary pigment colors required to produce a given color appearance and to describe a successful strategy for making such a prediction.

A complete lab write-up includes a Title, a Purpose, a Data section, a Conclusion/Discussion. The Data section should include the completed table. The Conclusion/Discussion section should include a thorough discussion of a strategy used to predict how to decide which primary pigments must be mixed to produce a given appearance.

### L9. Filtering Away Lab

Question:
What is the result of looking at various light colors through colored filters and what strategy could be used for predicting such results?

Purpose:
To observe the effect which various filters and combinations of filters have upon the incident light and to describe a useful strategy for predicting the results.

A complete lab write-up includes a Title, a Purpose, a Data section, a Conclusion/Discussion of Results. The Data section should include the provided table of observations. The Conclusion/Discussion should include a thorough discussion of a strategy used to predict what the result will be when a specific filter is used to filter a specific color of incident light.