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ERIC Number: EJ1037242
Record Type: Journal
Publication Date: 2013-Nov
Pages: 10
Abstractor: As Provided
Reference Count: 12
ISSN: ISSN-0031-9120
An RGB Approach to Prismatic Colours
Theilmann, Florian; Grusche, Sascha
Physics Education, v48 n6 p750-759 Nov 2013
Teaching prismatic colours usually boils down to establishing the take-home message that white light consists of "differently refrangible" coloured rays. This approach explains the classical spectrum of seven colours but has its limitations, e.g. in discussing spectra from setups with higher resolution or in understanding the well saturated colours of simple edge spectra. Besides, the connection of physical wavelength and colour remains obscure--after all, colour and wavelength are not equivalent. In this paper, we suggest that teachers demonstrate these impressive experiments in the classroom by using a video projector and a prism to disperse black-and-white slit images. We introduce experimental and diagrammatic methods for establishing the connection between the original slit image and the wavelength composition of the resulting spectrum. From this (or any other given) wavelength composition, students can systematically derive the colours with a simple RGB approach, thus gaining a more accurate picture of the relation between wavelength and colour.
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Publication Type: Journal Articles; Reports - Descriptive
Education Level: High Schools; Secondary Education
Audience: N/A
Language: English
Sponsor: N/A
Authoring Institution: N/A