IB PHYSICS Year 2
(SECONDARY)
ESSENTIAL UNIT 4 (EU4)
Atomic, Nuclear, and Particle Physics
(July 2015)
Unit Statement:
In this unit we consider the composition of atoms. We look at extra-nuclear electrons and the nucleus
and particles of which the nucleus is composed. We see the vast array of particles that are now known
to exist and how these particles can be classified and grouped. As is often the case, energy plays in
important role in the atom and fundamental to this is the tendency for particles to be most stable when
their energy is minimized.
Unit 4 provides the backbone for understanding the processes of nuclear fission and thermonuclear
fusion. A short review of the simple planetary model of the atom and the experimental evidence of the
model is followed by discussion about spontaneous decay, types of radiation and their effects,
transmutations, nuclear reactions and the mass-energy equivalency. This unit is the stepping stone for
the following unit.
This is one of the most important units in the syllabus. A large portion of the questions on paper 1, 2
and 3 will be based around this unit and the next unit, which is just a continuation of this unit. Doing
good or bad in this unit will in a large portion determine whether the student will do good or bad on
the final IB exam.
Essential Outcomes: (Must be Assessed)
1. TSW understand discrete energy and discrete energy levels (7.1 pp 268-270).
2. TSW describe the emission and absorption spectra of common gases and solve problems
involving atomic spectra, including calculating the wavelength of photons emitted during atomic
transitions (7.1 pp 270-273).
3. TSW describe the radioactive decay and complete decay equations of alpha and beta decay (7.1
pp 273-276).
4. TSW specify the unified atomic mass unit u (7.2 pp 282-284).
5. TSW solve problems involving mass defect and binding energy (7.2 pp 284-285).
6. TSW sketch and interprete the general shape of the curve of average binding energy per nucleon
against nucleon number (7.2 pp 285-286).
7. TSW describe nuclear fusion and nuclear fission, and solve problems involving the energy
released in radioactive decay, nuclear fusion, and nuclear fission (7.2 pp 286-289).
8. TSW describe the Rutherford-Geiger-Marsden experiment that led to the discovery of the nucleus
(7.3 pp 291-294).
9. TSW understand leptons, quarks, and their antiparticles (7.3 pp 294-297).
10. TSW specify the conservation law and apply conservation laws in particle reactions (7.3 pp 297298).
11. TSW understand the nature and range of the strong nuclear force, weak nuclear force, and
electromagnetic force and comparing the interaction strengths of the fundamental forces, including
gravity (7.3 pp 298-300).
12. TSW sketch and interpret simple Feynman diagram (7.3 pp 300-302).
Suggested Materials:
Textbook, Syllabus, Data Booklet, PSOW form,
Physics HL Investigations
IB Question Bank CD; topic Atomic & Nuclear Physics
Graphical Analysis software
Technology Resources:
YouTube: www.youtube.com – great resource
PhET computer simulations: Nuclear-fission, Rutherford-scattering, Alpha Decay, Beta Decay, etc.
http://phet.colorado.edu/en/simulations/category/new
Video about thermonuclear fusion:
http://www.youtube.com/watch?v=DyB7Ho_W9RE&feature=related
InThinking Subject Sites- where IB teachers go (Website by Chris Hamper):
http://www.thinkib.net/physics
Online Curriculum Center: http://occ.ibo.org/ibis/occ/guest/home.cfm
Destiny and Web Path Express (available through your library)
Online physics sites
These online resources present the same material as the notes on this Wiki in different ways. The
PhET Simulations site can be used for internal assessment ideas. The Physics Classroom Hyper
Physics PhET Simulations Khan Academy Physics Lectures Brightstorm Physics Lectures A-Plus
Physics with Fullerton
Suggested internal assessment for the unit:
4 hours of IA or more
Physics HL Investigations;
Investigation 23 – Half-life, Range And Energy Of Alpha Particles (Data based),
Investigation 24 – The Statistical Nature Of Radioactive Decay
Suggested Instructional Strategies:
It is often difficult to perform any laboratory exercise with radioactive decay. However, there are ways
to show what exponential decay means with simple models such as water leaking through a hole in a
bottle. The suggested simulations are very helpful and can be used for simple investigations.
Seeing a Geiger counter and hearing it registering the natural background radiation is worth million
words.
The students should be given examples of questions from previous IB exams.
Teachers should use questions and problems from the IB question bank.
Using the suggested PhET computer simulation(s) is strongly recommended.
Suggested assessment of mastery and beyond mastery of the unit:
It is strongly recommended that cumulative questions from past IB exams and from the IB question
bank are used for assessing mastery and beyond mastery.
Each TSW should be assessed with at least one question/problem. Some questions (for example
extended-response questions) can assess the mastery of more than one TSW.
B
To earn a B student will correctly answer
most questions that asses Lower Order
Thinking Skills (LOTS) and some questions
that assess Higher Order Thinking Skills
(HOTS).
SOME means at least a half
MOST means at least 55%
A
To earn an A student will correctly answer
most questions that asses Lower Order
Thinking Skills (LOTS) and most questions
that assess Higher Order Thinking Skills
(HOTS).
MOST mean at least 65%
Recommended predictive score can be calculated using weighted percentage of each unit score as
follows:
= Year 1*0.3 + (E01*1+E03*2+E04*3)/(1+2+3)*0.7
70%-100%: 7
60%-69%: 6
49%-59%: 5
38%-48%: 4
26%-37%: 3
65%-100%: A
55%-64%: B
For more detailed information on assessment of mastery and beyond mastery see the Suggested
Resources folder.