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How to use the OAPT Physics Contest

Roberta Tevlin, OAPT Newsletter Editor, Physics Teacher Danforth CTI
Roberta.tevlin@tdsb.on.ca

Recently, a teacher asked me for advice about how to start running the OAPT physics contest. I asked some teachers to help me answer this question. As well as finding great advice for getting students to write the contest, I also learnt about other contests and how teachers were incorporating past OAPT contest questions into their course all year long.

I would like to thank all the teachers who responded to my request for information: Deryk Jackson (Danforth CTI), Sandy Evans (Northview Heights SS), Gabrielle Kauffman (Bishop Allen Academy), Elzbieta Muir (Albert Campbell CI), Susan Hewitt (Lisgar CI), Martin Furtado (St. Ignatius High School), Eva Muresan (Mentor College), Gavin Kanowitz (AY Jackson SS) and Luciano Pattara (Martingrove CI).

What sorts of students will benefit most from writing the OAPT contest?
Teachers felt that the contest could be written by all of their grade 11 physics students because it covers the standard grade 11 curriculum. They felt that it was sufficiently challenging to prevent their top students from getting complacent, but it was not so difficult that it would discourage students from taking grade 12 physics.

What other physics contests do your students write?
They recommended that grade 9 and 10 students do the Michael Smith Challenge and that grade 11 and 12 physics students do the McMaster Contest.

Many teachers also run the Waterloo SIN Exam but they warned that it has become harder every year and may only be appropriate for a few grade 12 students.

One teacher also suggested the CAP Contest and said that it was very challenging and followed the grade 12 IB curriculum and also the AAPT Physics Bowl for grade 11 and 12 saying that it was similar to OAPT but more time pressured.

Advice for teachers trying the contest for the first time
For your first year, consider inviting just a few of your top students to write. This will make it easier to run. Warn your students this is a contest not a test. The average mark is below 50% and some of the material may not have been covered yet. Do the computer version for the immediate automatic feedback. However, have paper versions as a back-up just in case. You can give these to the students at the end of the day as a souvenir.

How do you get students to buy into this extra challenge?
The teachers said that for many students, the opportunity to compete in a larger arena was all the motivation that was needed. However, some schools have a plaque that recognizes the school’s top scorer each year; others use cookies or bonus marks and one teacher personally hand-crafted ceramic mugs as prizes!

How do you prepare students?
Some teachers run the contest without any preparation but others mentioned how they ran special sessions at lunch or after school using past tests. Several teachers said that they use past contests as a review of their course and many mentioned that they use contest questions throughout the year as part of their course. There are thousands of past OAPT contest questions sorted by unit at http://www.oapt.ca/resources/contestQB.html.

OAPT Contest questions for learning all year long!
Many of the questions lend themselves really well to the Peer Instruction technique developed by Eric Mazur of Harvard. In this technique, students need to select an answer from a multiple-choice question and then they have to explain their reasoning to the students sitting next to them — a specific version of think, pair, share. Providing a limited set of choices can often stimulate deeper and longer discussions than an open question. This student discourse can help remove common misconceptions, especially if it goes through several iterations.

As one example, consider mass and weight. Your grade 11 students have spent the first 15 years of their lives treating mass and weight as synonymous. In order to see why we need two different concepts, you can show videos of the astronauts on the Moon and discuss what is the same and what is different. Then you can use questions from the OAPT Contest Question Bank: Forces Unit. Here are two examples:

Suppose that a hole were drilled to the centre of a uniform solid spherical planet. A stone is dropped into the hole. When the stone is at the planet’s centre, compared with its values at the surface, you might expect that the stone’s

A) mass and weight are both unchanged.
B) mass and weight are both zero.
C) mass is unchanged and its weight is zero.
D) mass is zero and its weight is unchanged.
E) weight cannot be determine anywhere with this information.

Answer: C


A bowling ball is tied to a rope such that the rope lifts the ball straight up at a constant velocity. The magnitude of the tension in the rope is

A) greater than the force of gravity on the ball.
B) equal to the net force acting on the ball.
C) less than the force of gravity on the ball.
D) equal to the mass of the ball times its acceleration.
E) equal to the force of gravity on the ball.

Answer: E


As well as using the questions as they are, you can make modifications to the questions because they are provided in Word format. Consider the following question:

A 2.0 kg block of wood is dragged across a rough level floor at a constant velocity of 3.0 m/s by a horizontally applied force of 10 N. Compare the magnitudes of Fa to Ff and Fn to Fg.
edge
A)
Fa > Ff and Fn = Fg
B)
Fa < Ff and Fn = Fg
C)
Fa = Ff and Fn = Fg
D)
Fa > Ff and Fn > Fg
E)
Fa < Ff and Fn < Fg

Answer: C

After doing this question as is, you could explore mass and weight by asking the students what will change if this block is pulled with the same applied force on the Moon. You could make this an open, whiteboard discussion or you could make some new concept questions from it. Here are a couple of possibilities:

Which forces will be changed to 1/6th of their Earth value, when pulled with the same force on the moon?
A) Weight
B) Normal
C) Friction
D) Weight and normal
E) Weight, normal and friction

Answer: E


What will the acceleration of the block be?
A) 0 m/s2
B) 1/6
Fa ÷ m
C) 5/6
Fa ÷ m
D)
Fa ÷ m
E) 5
Fa ÷ m

Answer: C

How to get more involved in the OAPT
Every year we need to come up with thirty more questions for the competition and we need to make sure that the questions and answers are clear and varied in difficulty and type. This is an easy way to help the OAPT and volunteers are always welcome. If you are interested, please contact the editor Saara Naudts.
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