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Question
Show that the entire Paschen series is in the infrared part of the spectrum. To do this, you only need to calculate the shortest wavelength in the series.
The shortest wavelength in the Paschen series is $820 \textrm{ nm}$, which is greater than the shortest infrared wavelength. This means the entire Paschen series is in the infrared part of the spectrum. (By the way, it might be worth testing whether the longest wavelength emission in the Paschen series, for $n_i = 4$ is actually in the microwave or radio part of the spectrum).
Solution Video