Optical Phenomena and Properties of Matter (Grade 12 NSC Matric Physical Sciences): Flashcards

Pattern of specific wavelengths emitted by excited atoms

Dark lines when white light passes through cooler gas

Transitions ending at n=2 (visible light)

n=1, lowest energy level

$\Delta E = E_f - E_i$ (energy difference between levels)

Ultraviolet, transitions ending at n=1

Infrared, transitions ending at n=3

Exact inverse; same wavelengths, opposite processes

Object moving away; wavelengths appear longer (redder)

Its energy levels match infrared wavelengths; absorbs IR