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Description
The programme begins with a review of travelling and standing waves and goes on to examine the idea that electrons, protons and neutrons can be seen in terms of standing waves. This leads to a desc...ription of eigen wave functions and energy levels.
Metadata describing this Open University video programme
Module code and title: S101, Science: a foundation course
Item code: S101; 30
First transmission date: 02-10-1979
Published: 1979
Rights Statement:
Restrictions on use:
Duration: 00:24:00
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Producer: John Stratford
Contributors: Graham Farmelo; Barrie Jones; Peter Twinn
Publisher: BBC Open University
Keyword(s): Eigen wave function; Standing wave; Travelling wave
Subject terms: Diffraction
Footage description: Barrie Jones introduces the programme. Jones creates free travelling waves of various frequencies and wavelengths by manipulating a rope. He then goes on to create confined wave with another rope and points out the difference between standing and travelling waves. Graham Farmelo performs an experiment in which the wavelength of an electron diffraction pattern on a fluorescent screen is changed by altering the voltage at the electron gun. This behavior is similar to that found in travelling waves. Using a model and animations, Farmelo demonstrates the behaviour of an electron confined between two parallel reflecting plates. He introduces the concept of eigen wave functions which describe standing probability waves. Farmelo goes on to explain how the standing wave functions are related to specific energy levels for electrons. Barrie Jones performs an experiment in which the spectral lines of a sodium vapour light source are examined using a spectrometer. An animated diagram demonstrates how spectral lines depend on the energy levels of electrons in the sodium atoms. Jones goes on to explain how the sodium vapour lamp works. He uses an animation and sounds a gong to illustrate his points. Jones goes on to show how the differences between energy levels of electrons can be measured. We explains the principles behind the method used. Graham Farmelo discusses the energy levels of confined neutrons and protons in the nucleus of an atom. He explains a method for measuring difference between nuclear energy levels. Peter Twinn, at Liverpool University, describes work done there on studying the structure of magnesium 26 atoms by examining their energy levels. He explains the experimental work in some detail. Shots of the apparatus with commentary (v/o) by Barrie Jones. The magnesium 26 experiment is set up and an animation is shown to explain what is happening. Commentary (v/o) by Farmelo and Jones. The experiment is run. Shots of the experimental apparatus while it runs. Commentary (v/o) by Jones. The data is shown on a VDU in graphic form. Jones analyses the data and arrives at a value for one energy level. Jones goes on to explain how the rest of the energy levels are determined from the data. Shots of the Liverpool research team studying and discussing the data. Barrie Jones sums up the programme.
Master spool number: HOU3130
Production number: FOUS030Y
Videofinder number: 1205
Available to public: no