© ATOM 2012 A STUDY GUIDE by Katy marriner & Eryn o’mahony
http://www.metromagazine.com.au
ISBN: 978-1-74295-148-5 http://www.theeducationshop.com.au Driven to Diffraction
Written and directed by Richard Jasek for Above L-R: Stephen Sheehan as William Lawrence Bragg in a still from the film Kojo Productions.
This study guide ‘It is with a feeling of awe that we has been written for secondary students at examine the new science.’ all year levels. This guide provides – William Henry Bragg information and suggestions for learning activities in riven to Diffraction tells the story of Use your notes to write an advertisement for Biology, Chemistry, father and son physicists, William Henry a scientist that would appear in the employ- History, Laboratory Skills Certificate 111, Bragg and William Lawrence Bragg. Part ment section of a newspaper. D Media, Science and human interest story and part science lesson, the After you have watched Driven to Diffraction, Physics. Driven to documentary explores the discoveries and legacy review the draft of your advertisement. What Diffraction is also an of the Nobel Prize winning duo. Regarded as two do you need to change? excellent resource of the most important scientists of the twentieth for use by Science faculties to support century, the Braggs’ development of X-Ray Famous scientists: a research project professional learning. crystallography made possible an astonishing for Years 7 and 8 list of scientific advancements in DNA, cancer The Australian therapies, solid state electronics, modern • Can you name any famous scientists? Why Curriculum: Science provides pharmaceuticals and radio astronomy. are they famous? opportunities for Had you heard of William Henry Bragg and students to develop As a classroom resource, Driven to Diffraction pro- William Lawrence Bragg before watching an understanding motes the importance of understanding science Driven to Diffraction? of important and highlights science as a human endeavour. • William and Lawrence Bragg are often science concepts and processes, the referred to as Australian scientists, even practices used to What’s a scientist? though William was not born in Australia and develop scientific Lawrence only spent his childhood and ado- knowledge, of • Describe your perception of a scientist. What lescence in Australia. science’s contribution do they look like? What do they wear? Where Can you name any other Australian scientists, to our culture and society, and its SCREEN EDUCATION © ATOM 2012 would they work? What would they do for past and present? What contributions have applications in our leisure? they made to scientific understanding? lives. The story of Do William and Lawrence Bragg fit with your • Working with a partner, make a digital story William and Lawrence perception of a scientist? about the achievements of another Australian Bragg as told in • What skills and qualities do you need to be a scientist. Your subject may be a scientist from Driven to Diffraction reflects these scientist? the past or the present. understandings. Discuss your answer to this question with • Why is it important to know the history of others in the class. Science? DURATION: 55 min
2 Introducing Introducing Introducing William Henry Bragg William Lawrence Bragg Gwendoline Bragg
William Henry Bragg was born on William Lawrence Bragg was born Born in 1871 in Adelaide, South 2 July 1862 in Cumberland, England. on 31 March 1890 in Adelaide, South Australia, Gwendoline Todd was the Australia. daughter of Charles Todd, Postmaster • What do we learn about William General and Government Astronomer Bragg’s childhood and adolescence Lawrence Bragg received his elementary of South Australia. in Driven to Diffraction? Why are education at St. Peter’s College and these details important? entered Adelaide University in 1904 to In 1889, she married William Bragg. study mathematics, chemistry and phys- They had three children, a son William Having graduated from Cambridge in ics when he was fifteen. He graduated Lawrence born in 1890, a son Robert 1885, William Bragg was appointed with first class honours in 1908. Charles born in 1891 and a daughter Elder Professor in Mathematics and Gwendolen Mary born in 1907. Physics at the University of Adelaide in When the family moved to England in Australia. During his time at the univer- 1909, Bragg entered Trinity College, Prior to her marriage to William Bragg, sity, Bragg became an able and popular Cambridge. After initially excelling Gwendoline studied painting at the lecturer. He encouraged the formation of in mathematics, he transferred to Adelaide School of Design. Both the student union, and the attendance, the physics course in the later years Gwendoline and her husband painted free of charge, of science teachers at of his studies, and graduated with landscapes in watercolours and exhib- his lectures. At the end of 1908, Bragg first class honours in 1911. In 1914, ited at the South Australian Society of returned to England. During Bragg’s Bragg was elected to a Fellowship at Arts in 1896. twenty-three years in Australia, he saw Trinity College. Bragg graduated from the number of students at the University Cambridge University with first class • View examples of Gwendoline of Adelaide almost quadruple, and honours in 1912. After finishing his Bragg’s watercolours at: was responsible for the development studies, he stayed on to work at the http://nla.gov.au/nla.pic-an5836938 of its excellent science school. Whilst Cavendish Laboratory at Cambridge http://www.friendsasa.com/sasa in Adelaide, Bragg played tennis and University. historyproject_Update.html golf, and as a founding member of the • What credit does Gwendoline Bragg North Adelaide and Adelaide University • What do we learn about Lawrence deserve for her husband and son’s Lacrosse Clubs, contributed to the intro- Bragg’s childhood and adolescence successes? duction of lacrosse to South Australia. in Driven to Diffraction? Why are these details important? • Detailed biographies of William • Detailed biographies of Lawrence Bragg can be read online at: Bragg can be read online at: http://adb.anu.edu.au/biography/ http://adb.anu.edu.au/biography/ bragg-sir-william-henry-5336 bragg-sir-william-henry-5336 http://en.wikipedia.org/wiki/ http://en.wikipedia.org/wiki/ William_Henry_Bragg William_Lawrence_Bragg SCREEN EDUCATION © ATOM 2012 http://www.asap.unimelb.edu.au/ http://www.asap.unimelb.edu.au/ bsparcs/exhib/nobel/braggw.htm bsparcs/exhib/nobel/braggl.htm http://www.eoas.info/biogs/ http://www.eoas.info/biogs/ P000252b.htm P001998b.htm http://www.nndb.com/ http://www.nndb.com/ Above L-R: William Henry Bragg, people/533/000099236/ people/538/000099241/ c. 1926; William Lawrence Bragg, c. 1906; Michaela Cantwell as Gwendoline Bragg 3 1
William Bragg’s early experiments 2 Radio waves him the first Nobel Prize in Physics in 1901. 3 William Bragg worked with his father-in-law Charles Todd to pioneer radio transmission Assisted by Robert Chapman and Arthur Rogers, in Australia. In his role as Superintendent of William Bragg’s attempts to replicate Röntgen Telegraphs, Todd was responsible for the building experiments pioneered Australia’s use of X-rays. of the overland single-wire telegraph line that William made the first X-ray tube in Australia. linked Australia to the rest of the world in 1872. When a six-year-old Lawrence fell from his His interest in communication technologies tricycle and broke his elbow, his father made use turned to radio transmission in the late 1890s. of the new technology. This incident is the first Bragg demonstrated Guglielmo Marconi’s radio 4 recorded surgical use of X-rays in Australia. technology in Adelaide in 1897, and then went to England to meet Marconi and learn more This is also an excellent example of how science about wireless transmission. In 1899, working and technology are interrelated. The glass tube with Arthur Rogers, Bragg sent the first wireless that William produced allowed him to apply his telegraph messages in Australia. scientific understanding and produce X-rays. The tube would have been produced by glass blow- • Radio is the transmission of signals from one ing. Glass blowing is a technique employed by place to another through the use of radio both scientists and artists. waves. Why was the discovery of radio waves • Watch the YouTube clip on glass blow- important? ing at
Wilhelm Conrad Röntgen was a German physi- Lawrence Bragg’s first SCREEN EDUCATION © ATOM 2012 cist. In 1895, Röntgen produced and detected discovery electromagnetic radiation in a wavelength range today known as X-rays. His achievement earned Lawrence Bragg’s first scientific discovery was the discovery of a species of cuttlefish. Sepia braggi was named in his honour. Bragg’s inter- 1: William Lawerence Bragg (left) with William Henry Bragg est in the natural sciences stemmed from the 2: William Lawrence Bragg, Cambridge 1915 considerable amount of time he spent alone in 3: Cambridge street scene 4: The DNA double helix the garden and walking along the beach.
4 This page: Scenes from the film, featuring Michaela Cantwell as Gwendoline, Brad Williams as William Lawrence and Stephen Sheehan as William Henry
It is common in science for a new species to be named after the person who made the discovery. Some scientists, however, name insignificant or ugly specimens after their enemies.
• Lepidocephalichthys zeppelini is a newly identified species of fish, named after Led Zeppelin. Information about how the species got its name can be ac- cessed at
Ionisation and the Bragg Peak Waves or particles? Inspired by the recent discoveries of radium and radioactivity by Pierre and Marie Curie, William William Bragg believed that X-rays were made up Bragg began his own research into ionisation. from particles whereas Charles Barkla proposed the theory that X-rays were due to waves. William Ionisation is the physical process of converting and Lawrence discussed these opposing views an atom or molecule into an ion by adding or for some time until Max von Laue’s X-ray dif- removing charged particles such as electrons or fraction experiment seemed to prove that X-rays other ions. were indeed waves. Scientists believed crystals were made up of regular repeating patterns. The The Bragg Peak is a pronounced peak on the problem was that there were some unexplained Bragg Curve that plots the energy loss of ionising patterns in Max von Laue’s data. Lawrence pon- radiation during its travel through matter. For dered this and eventually came up with a theory protons, α-rays, and other ion rays, the peak that explained these dots. occurs immediately before the particles come to rest. When a fast charged particle moves Lawrence believed that the crystal structure was through matter, it ionises atoms of the material made up of a series of sheets of atoms, laid one and deposits a dose along its path. The phenom- on top of another, with each sheet behaving like enon is exploited in particle therapy of cancer, to a mirror. So the intricate pattern of dots that were SCREEN EDUCATION © ATOM 2012 concentrate the effect of light ion beams on the produced by passing X-rays through a crystal is tumor being treated, while minimising the effect caused by a series of interactions in which the on the surrounding healthy tissue. X-rays are reflecting off the sheets of atoms and then some meeting up again forming dark dots • Why is ionisation important? while single waves were causing lighter dots. • Working as a class, make a list of real world applications of the Bragg Peak. From this experiment Lawrence formulated his Bragg equation, which connects the wavelength
5 1: Stephen Sheehan as William Henry with X-ray spectrometer 2: Green glow of the X-ray tube 3 & 4: The X-ray spectrometer
the structure of atoms. Later William and Lawrence Bragg were able to prove the at- oms were arranged in a lattice form that was an extension of Von Laue’s Theory. Do you think it was fair that Max Von Laue won a Nobel Prize when his theory wasn’t 100 per cent correct? Do you think that some current scientific theories that we believe today may be proven to be incorrect in the future? 1 • Lawrence Bragg based his theory on data from Max Von Laue’s experiment that showed lighter and darker dots. Will all scientists come to a similar conclusion when given the same data?
X-ray Crystallography and X-ray Spectroscopy
‘It was a glorious time … We worked far into the night with worlds unfolding before us. It was like discovering a new goldfield where nuggets were just waiting to be picked up from the ground.’ – Lawrence Bragg
William and Lawrence Bragg were a powerful combination, as between them they had com- 2 bined expertise in both technology and science. William had extensive background in design- ing machines and technology so he designed of X-rays (λ), the distance between successive the X-ray spectrometer, a device that could sheets of atoms in a crystal (d) and the angle at examine the reflections of X-rays from crystals. which the X-rays strike these sheets (θ). Or as Lawrence’s mathematical and science ability was the equation states: nλ = 2d sinθ where n is a essential for analysing all the data they collected. whole number. Together they showed how it is possible to iden- • For further explanations of Bragg’s law, visit: tify the structure of a crystal by passing X-rays http://en.wikipedia.org/wiki/Bragg%27s_law through it and examining the pattern of dots that http://hyperphysics.phy-astr.gsu.edu/hbase/ are produced by the reflected rays. quantum/bragg.html http://www.eserc.stonybrook.edu/ • How do you think William and Lawrence ProjectJava/Bragg/ Bragg felt when they were working out the http://www-outreach.phy.cam.ac.uk/camphy/ structure of various crystals? xraydiffraction/xraydiffraction_exp.htm • Advances in scientific understanding often • Scientific understanding, including models rely on developments in technology and and theories, are contestable and are refined technological advances are often linked to 3 over time through a process of review by the scientific discoveries. scientific community. Describe a modern scientific invention that is SCREEN EDUCATION © ATOM 2012 Describe a time when you and a classmate based both on science and technology. had a different point of view. How did you • What is Rational Drug Design? Explain the resolve your disagreement? link between X-ray crystallography and ra- How did William and Lawrence Bragg resolve tional drug design. the issue when they both had different theo- ries to explain the nature of X-rays? Diffraction manifests itself in the apparent bending Max Von Laue won a Nobel Prize for his of waves around small obstacles and the spread- 4 discovery on the nature of X-rays and ing out of waves past small openings. Diffraction
6 provides a powerful tool for studying the geometry Above: Brad http://nobelprize.org/educational/nobelprize_ of objects that are too small to be viewed directly. Williams as info/gradeschool.html One of the most famous historical cases was the William Lawrence http://nobelprize.org/mediaplayer/index. revealing of the double helix structure of DNA. (left) and Stephen php?id=1335 Sheehan as • Who discovered the structure of DNA? William Henry Physics was the prize area that Alfred Nobel Who was Rosalind Franklin? Why is she mentioned first in his will. At that time, in the end significant? of the nineteenth century, many people viewed What role did William and Lawrence Bragg physics as the foremost of the sciences. His own play in this scientific discovery? research was also closely tied to physics. In 1901 Who else should be given credit for the dis- the very first Nobel Prize in Physics was awarded covery of the structure of DNA? to Wilhelm Röntgen for his discovery of X-rays. Begin your research online at: http://nobelprize.org/educational/medicine/ • Visit Nobelprize.org at
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1 Sound ranging
Bragg, in recognition of their services in pro- Lawrence Bragg’s research work was inter- moting the investigation of crystal structures by rupted by both World War One and World War means of X-rays. Two. During both wars, he worked on sound ranging methods for locating enemy guns. • Information about the Braggs’ Nobel Prize for Physics can be read online at
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2 1: The Royal The Royal Institution of Institution of Great Britain and The Royal Australia, Adelaide Institution of Australia • Why are institutes like the RI in Australia and 2: Michaela Britain important? Cantwell as ’Don’t talk to them about science, show it to • The RI is well known for its public science Gwendoline them.’ – Lawrence Bragg program, including the annual Christmas Lectures. The lectures, originally founded The Royal Institution of Great Britain (RI) was es- by Michael Faraday, are given by notable tablished in London in 1799. Its aim was then, as scientists and are a means to teach adults it is now, to facilitate scientific education and to and children about the science of everyday provide opportunities for scientific discovery and things. A video archive of the lectures can be research. William Bragg became Superintendent accessed at
9 Legacy
‘The important thing in science is not so much to obtain new facts as to discover new ways of thinking about them.’ – William Henry Bragg
• Do you think that the contribution of ‘popular William Bragg died in 1942, aged 79. scientists’ counts? Lawrence Bragg died in 1971, aged 81. Their • Working with a peer, teach your class discoveries shaped and continue to shape sci- something about the science of everyday entific knowledge. The Braggs worked in the things. Your presentation may be submit- area of physics yet their discovery has lead to ted in the form of a podcast, PowerPoint, many advances in other branches of science. demonstration in front of the class, magazine column, web page, blog or video clip. Need The influence of the Braggs is evident in the inspiration? Begin your research at
10 SCREEN EDUCATION © ATOM 2012 11 vour Science As A Science Endea Human Peter: Clip 2 runs from 37.03 – 38.22. It begins Peter: Clip 2 runs from 37.03 – 38.22. with the title card ‘Credit’ Why did father and son make a good team? Were there there Why did father and son make a good team? Were any drawbacks to the partnership?
Science knowledge can develop through collaboration and Science knowledge can develop through the disciplines of science. connecting ideas across Driven to Diffraction: the following clip from Watch • Scientists Working in Teams
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W W Peter: Clip 1 runs from 12.22 – 15.01. It begins Peter: Clip 1 runs from 12.22 – 15.01. Development’ with the title card ‘Lawrence’s How do you think other scientists felt when Lawrence How do you think other scientists felt when Lawrence Bragg won the Nobel Prize at age twenty-five? Compare Lawrence’s childhood with other children of childhood with other children Lawrence’s Compare that time. means to describe the things that Remember compare similar and what is different. are • Answer the questions in the space provided. • Like father, like son Like father, receive a Nobel the first Australian to Bragg was Lawrence is also the youngest person to ever Prize for Science. He a Nobel Prize. receive . Driven to Diffraction the following clip from Watch NAME: SCREEN EDUCATION © ATOM 2012 12 vour Science As A Science Endea Human Name those scientists who were mentored by William mentored Name those scientists who were name, Bragg. Next to each scientist’s and Lawrence and the branch of sci- state what he or she discovered, ence in which he or she worked. How are scientific ideas communicated in the twenty- scientific ideas How are first century?
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W W How were scientific ideas communicated during the time How were significant discoveries? Bragg’s of William and Lawrence How important was it for William and Lawrence Bragg to How important was it for William and Lawrence communicate with other scientists? • • NAME: SCREEN EDUCATION © ATOM 2012 13 vour Science As A Science Endea Human Can you think of an example of when a scientific Can you think of an example of when a lives? on people’s discovery has had an adverse effect Science discoveries have the potential to improve the have the potential to improve Science discoveries quality of human life. the Braggs’ discoveries improved In what ways have the quality of everyday life?
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Driven to Diffraction is available on DVD from Ronin Films PO Box 680 Ph: (02) 6248 0851 Mitchell ACT 2911 Ph: (02) 6249 1640 AUSTRALIA [email protected]
This study guide was produced by ATOM. (© ATOM 2012) ISBN: 978-1-74295-148-5 [email protected] For more information on Screen Education magazine, or to download other study guides for assessment, visit
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