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 Chapter 21
Atomic physics
LEARNING OBJECTIVES
In this chapter you will learn how to:
âunderstand the discovery of the atomic nucleus in the GeigerâMarsdenâRutherford experiment.
âdescribe and explain gas emission and absorption spectra in terms of energy levels.
âsolve problems with atomic transitions.
understand the consequences of a quantised angular momentum in the Bohr model for hydrogen.
GUIDING QUESTIONS
âWhy is energy in atomic systems discrete?
âWhat is matter made out of?