IB PHYSICS – Year 1
(SECONDARY)
ESSENTIAL UNIT 5 (E05)
Circular motion
(July 2015)
Unit Statement: When an object moves in a circular trajectory, no matter whether the motion is
happening at a constant speed or not, the net force acting on the object is not zero Newtons. Circular
motion is always accelerated. Man cannot travel beyond the Earth without knowledge of circular
motion.
Essential Outcomes: (must be assessed for mastery)
1. The Student Will state the definition of angular displacement, angular speed, period and
frequency and state the difference between angular and linear speeds (6.1 pp 246-249).
2. TSW draw a vector diagram to illustrate that the acceleration of a particle moving with constant
speed in a circle is directed towards the center of the circle and apply the expression for centripetal
acceleration and centripetal force (6.1 pp 249-252).
3. TSW qualitatively and quantitatively describe examples of circular motion: Satellites in orbit,
Amusement park rides, Turning and banking involving cases of vertical and horizontal circular
motion (6.1 pp 252-257).
Suggested Materials:
Textbook, Syllabus, Data Booklet, PSOW form, Physics Core Investigations
IB Question Bank CD; topic Circular motion
LogerPro (Vernier software) and probes
Graphical Analysis software
Technology Resources:
PhET computer simulations: Ladybug revolution (for showing direction of centripetal acceleration),
http://phet.colorado.edu/en/simulations/category/new
Online Curriculum Center: http://occ.ibo.org/ibis/occ/guest/home.cfm
InThinking Subject Sites- where IB teachers go (Website by Chris Hamper):
http://www.thinkib.net/physics
Destiny and Web Path Express (available through your library)
Suggested internal assessment for the unit:
2 hours of IA or more
Physics Core Investigations (In the Suggested Resources folder):
Investigation 7 – Uniform Circular Motion
Suggested Instructional Strategies:
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.
A demonstration of natural phenomena is a great way to introduce a new topic.
Hands on activities in which students collect and analyze data are encouraged.
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:
=(E01*1+E02*2+E03*3+E04+E04*4+E05*5)/(1+2+3+4+5)
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.