CD spectrograph


Cold open was Niki Indigo with no comment. Slips of paper were prepared ahead of class. The students were beckoned outside non-verbally.

Niki with the new speakers really thumps

Once outside I told them to write down the colors they see in the order they see the colors.

Students listed from four to eight colors. 

This activity segues into ROYGBIV and the issue of six colors versus seven and  of indigo. Whether this is the optimal direction to take this activity is debatable. There may be other less potentially problematic directions to go. Such as the wavelengths and frequencies of the colors. Short shrift can be made of indigo saying Newton preferred seven colors but not delving into the possible reasons.

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