How to measure cleanliness

[deleted-35425]

I am helping my little sister with her science fair project and we are testing whether the cost of laundry detergent effects how well it removes stains. My problem is, I can't figure out how to numerically measure the results. We are going to stain three pieces of fabric with ketchup, mustard, and grass for each detergent and then agitate them in a solution of water and detergent. I cannot figure out how to measure the results in a method that will allow the measurements to be graphed as data. Any help would be greatly appreciated. Thanks. Honi

[deleted-71417]

Hi,

You are trying to quantitate the colors of stained and unstained cloth before and after washng in detergent solutions, if I understand your question. I found this aplet that might help:

http://home.comcast.net/~ed-abramson/14 ... olors.html

This tool will generate colors that you could compare to the color of your sample pieces until they match as closely as possible. The aplet then shows you numerical descriptions of the color that matches. It should then be possible to graph the difference of the color descriptors between the cloth sample before staining, after staining, and after laundering. I think you will be able to devise a scale to show you about how much stain has been removed by laundering.

This sounds like a fun project! Good luck with it!

Barrett Tomlinson