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# DE - SCI-270 Guide

## Work on Problems in the Tasks and Submit Them

The Tasks provide problems for you to test your understanding and enhance your learning. Some problems involve evaluation of quantities, and for them please provide the final values, not formulas, at the space provided.

Once you have submitted your answers to the Tasks, you will receive a file that gives you hints on how some of the problems can be solved. Thus, you will not be notified of any error in your submitted results.

## Regarding one-minute summaries (OMS)

Over the past years, students asked questions in their one-minute summaries (OMS). The following are some questions and my responses. These may be of interest to you and you may read them if you have the time.

## Final Exam Information

The final examination consists of 50 to 60 multiple choice questions. Please bring you calculator for the exam. The Data Sheet on the inside cover of the Lecture Notes will be supplied during the final examination.

Final examinations test your understanding of the concepts, your knowing of facts, and your ability to apply these concepts and theories to solve problems including calculation of quantities.

The Midterm example gives some questions that I have set a few years ago for the Campus Course. You may get some clues regarding how the questions are made up from these examples. Of course, the questions in the Quizzes and Tasks are also examples of questioning style in the final. Doing the Tasks and Quizzes honestly is a practice for your final examination.

## The Quiz Guide

Writing the quizzes is a self assessment, not work to be done. Please write the quizzes as if you are writing an examination. Each quiz is designed to be finished in less than 15 minutes.

The computer system seldom marks your answer incorrectly. The system has been tested for several years.

After you have answered the question, the system gives you a Hint. The Hints are not answers, but suggestions as to how to solve the problem. Please use it to learn the theory involved in the question. I hope they are helpful for discovering your error.

Error = (Answer - YourAnswer)/Answer If the Error is less than 3-5% (0.03 to 0.05), YourAnswer will be accepted as correct. If the question requires a rather precise answer, I usually set Error < 3% as the limit; otherwise Error < 5% is the limit.

Please enter very large or small numerical answers in the format #.##e## or #.##E##. On the other hand, values such as 102345678, 1.02e8, 1.023E08, and 1.023e+08 are accepted by the Quiz system. For very small values such as 1.23x10-23 should be entered as 6.023e-23 or 6.023E-23

The deadlines for quizzes set a schedule for you to acquire skills gradually for building a solid foundation. Please write your quizzes a few days before the deadlines so that you may get help in case something goes wrong.

After a quiz, assess your strength and weakness. Please find ways to improve your learning rather than trying to maximize your quiz mark. Up to 5% deduction may apply if your quiz marks are > 90% but your final examination mark is < 60%.

If your computer freezes or you suspect your quiz mark not properly recorded, please re-write the quiz (again). The computer system will decide to allow or not to allow you to write.

Usually, a mark is assigned according to the performance at the time. Writing a quiz is a performance. A mark is assigned with certain rules, not just providing an answer. Certain procedures must be implemented in Quizzes Over the Internet in order to be fair to all students. Please follow the procedures.

## Quiz Outline

##### Click the individual Quiz for the Quiz Page. Topics or concepts to be tested are listed below each Quiz.
1. Energy - 2009/05/21@16:00HR <== Deadline
• explain the concept of energy
• interconvert mechanical energy and heat
• describe temperature and heat
• evaluate electric energy
• interconvert power and energy
• explain sound
• evaluate energy of electromagnetic radiations
• interconvert mass and energy

2. Discoveries of X-rays and radioactivity, and atomic structures - 2009/05/28@16:00HR <== Please write the quiz a few days before the deadline.
• identify natural units
• apply atomic and molecular weight, Avogadro's number and moles in calculations
• describe charges and properties of electrons
• explain spectra
• interpret the hydrogen spectra

3. Structure of the Atom and X-rays - 2009/06/04@16:00HR <== Please write the quiz a few days before the deadline.
• discovery of X-rays
• Moseley's law and atomic structures
• Rutherford's and Bohr's atomic model
• quantum mechanical concepts
• nucleons and nuclide
• summarize the standard model

• calculate number of atoms in a sample
• evaluate radioActivity A, half_life, t1/2, decay constant dk and amounts of samples using A = dk * number_of_atoms Know the relationsip between decay_constant and half_life
• be able to calculate radioactivity as a function of time
• write equations for transmutation of nuclides in decay processes
• the four families of decay series
• explain internal conversion, Auger electrons, isomeric transitions etc.
• transmutation of nuclides
• estimate decay energy, including the maximum kinetic energy of beta particles

5. Particles and Nuclides - energy states - 2009/06/18@16:00HR
• describe the concept of particles and antiparticles
• explain energy aspects of particles and antiparticles
• explain how positron was discovered
• specify properties of antiparticles - particularly positrons
• explain annihilation reactions
• describe the standard model in terms of fundamental particles
• show organization and components of mesons
• forces and force carriers
• understand Fynman diagrams
Nuclides - energy states
• evaluate the binding energy (BE) of a nuclide
• tell nuclide with zero BE
• evaluate mass excess (ME) of a nuclide
• tell nuclide with zero ME
• evaluate decay energy
• estimate decay mode
• predict the stable isobar(s)
• estimate max kinetic energy of beta or positrons in beta decay

6. Nuclear Reactions - changing nuclei - 2009/06/25@16:00HR
• nuclear reactions, notations and changes
• potential energy during a nuclear reaction
• apply conservations of nucleon and charges to nuclear reactions
• explain nuclear-reaction experiments
• evaluate cross sections, reaction rates, and beam intensities
• estimate energies in nuclear reactions

7. Nuclear Fission - energy for war and peace - 2009/07/02@16:00HR
• discovery of n-induced fission, fission products, fission energy, fission crossections, nuclear model for fission
• estimate (calculate) fission energy for certain fission products
• nuclear reactors, types, moderator, control rod, fission yield
• estimate quantities of natural uranium required for the production of fission fuel
• natural nuclear reactor, reactor accidents, and their impacts

8. Nuclear Fusion - powering the universe - 2009/07/09@16:00HR
• fusion reaction
• estimate fusion energy
• fusion cross section of various fusion reactions
• fusion in stars and life of stars
• plasma and fusion
• fusion bombs and fusion research

9. Ionizing Radiation - safety - 2009/07/16@16:00HR
• describe interaction of ionizing radiation with matter
• define stopping power, range, annihilation, bremsstrahlung radiation, Compton effect etc.
• estimate speed from energy of particles and relativity mass
• describe the mechanisms by whichd high-energy electrons and gamma rays lose energy
• describe how ionization, proportional, and Geiger-Muller detectors work
• explain how solid state detectors and scintillation detectors work
• explain how cloud and bubble chambers work and what they are used for