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Chapter 4: From Blackbody to Bohr
The late 1800s and early 1900s saw physics move from the classical period (described by Newton's laws and Maxwell's equations) to what we now call modern physics (explained by special relativity and quantum theory). The shift to a quantum theory was prompted by a series of experiments that could not be adequately explained classically. These experiments include blackbody radiation and a number of experiments that placed the atom on center stage. This period also marks the beginning of our current understanding of the fundamental structure of matter. This chapter describes these experiments and developments ends with the Bohr model of the atom or the so-called old quantum physics. While the Bohr model and the other models were amazingly successful at explaining a number of atomic properties, the observations these models could not explain hinted at the need for a better theory (quantum mechanics).
Table of Contents
- Section 4.1: Blackbody Radiation.
- Section 4.2: Exploring Wien's Displacement Law.
- Section 4.3: Brownian Motion.
- Section 4.4: Exploring the e/m Experiment.
- Section 4.5: Exploring the Millikan Oil Drop Experiment.
- Section 4.6: Thomson Model of the Atom.
- Section 4.7: Exploring Rutherford Scattering.
- Section 4.8: The Bohr Atom and Atomic Spectra.
- Section 4.9: Exploring the Emission Spectrum of Atomic Hydrogen.
- Problem 4.1: What is the temperature of the object?
- Problem 4.2: Rank the objects according to their temperatures.
- Problem 4.3: Determine charge to mass ratio of unknown particle.
- Problem 4.4: Determine the charge on a drop in the Millikan Oil Drop Apparatus.
- Problem 4.5: Find the distance of closet approach in Rutherford Scattering.
- Problem 4.6: Determine the charge of the nucleus in a Rutherford Scattering Experiment.
- Problem 4.7: A Bohr atom undergoes a transition.
- Problem 4.8: Energy level transitions matched with spectral lines.
- Problem 4.9: Identify the absorption spectrum of hydrogen.