Answer:
This above is slightly true though there are some things that need improved. My class is working on this project and here are some facts that will help with light filtering.
All light colors produce different Wavelengths and are measured in Nanometers, the wavelengths are as follows:
Red 700-750 NM
Orange 600-700 NM
Yellow 560-600 NM
Green 500-560 NM
Blue 430-560 NM
Purple 380-430 NM
All these wavelengths are absorbed by the plants and will allow the plant to grow. Carl Gelenye has worked with these light filters and has extensive data on them and their effect on plants.
Based on a previous year's work green was alright, Violet however was the best, blue was the worst.
If you wanted to test which filter works best I suggest using "Wisconsin Fast Plants" which grow in about 1 week and need only direct light, water, and fertilizer http:/www.fastplants.org
These plants are the same kind my class is using for our experiments.
and to answer the actual question put up "Why will different colored light effect a plant growth?" it is because the light is absorbed and processed into energy for the plant. the difference in wavelengths can alter this process ever so slightly which causes the plant to react differently. also plants tend to grow towards the light produced and the color difference can alter this action as well.
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