Revisiting the round bottom flask rainbow experiment
Physics Education
2017-01-02 v1 Atmospheric and Oceanic Physics
Abstract
A popular demonstration experiment in optics uses a round-bottom flask filled with water to project a circular rainbow on a screen with a hole through which the flask is illuminated. We show how the vessel's wall shifts the second-order and first-order bows towards each other and consequentially narrows down Alexander's dark band. We address the challenge this introduces in producing Alexander's dark band, and explain the importance of a sufficient distance of the flask to the screen. The wall-effect also introduces a splitting of the bows which can easily be misinterpreted.
Cite
@article{arxiv.1612.09563,
title = {Revisiting the round bottom flask rainbow experiment},
author = {Markus Selmke and Sarah Selmke},
journal= {arXiv preprint arXiv:1612.09563},
year = {2017}
}