On the way one of the beams in Young's experiment put a tube length of 2 m with plane bases. When filling the tube with chlorine all the interference pattern on the screen shifted to 20 bands. Calculate the refractive index of chlorine, assuming that the refractive index of air 1.000276. Wavelength 589 nm.

Detailed solution shorthand terms, formulas, laws used in the decision, the withdrawal of the calculation formula and the response.
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