November 10, 2022 Filed in: Articles
Chris Meyer, York Mills C.I., Toronto District School Board
Pride comes before the freefall
What topic could be easier, right? It’s just straight up and down — no funny business. Freefall is the poster child of constant acceleration, everyone’s go-to example. We can teach this in our sleep! But we might not realize that we are setting up our students for a physics ambush. While our students’ first freefall problem might seem straightforward and understandable, the second one often contains a trap!
Second freefall problem: “You drop a ball from a window 1.9 m above the ground. How much time does it take to hit the ground?” The student sizes up the problem; it seems easy. The displacement is 1.9 m downward. The acceleration is known; the student is feeling confident. They can find the time if they know one more motion quantity. Ah, the final velocity is zero! Problem solved!
And thus, the unsuspecting student is ensnared in the most common trap of freefall motion. This highlights the real challenge of understanding freefall: students need a genuinely sophisticated understanding of forces to make use of freefall ideas. Emphasizing freefall before studying forces allows students to tumble into numerous, all-too-common learning traps. Let’s nimbly dodge these traps and explore a better way to study freefall! Read More...
October 22, 2022 Filed in: Articles
Orbax, Production Specialist for Physics Education Content, Department of Physics, University of Guelph
Greetings educators! Orbax here from the Department of Physics at the University of Guelph.
When I went to university for physics in the late 90s, “science communication” as we know it now did not exist. Our science communicators were there, but it seemed like it was much more of a journey to find them then than it is now. Television (both high-end productions and cable access), radio, print media… these were the ways in which we found science communication mostly born out of a necessity to demystify some of the more obscure elements of our profession as well as a way to combat some of the pseudoscience that was rampant in the media. Read More...
October 07, 2022 Filed in: Articles
Kim Jones, Associate Professor of Chemical Engineering at McMaster University
question students have been asking for generations, in math classes, in science classes, and definitely in Physics classes… “Miss, when am I going to use this?” They rub their faces and pull on their hair in despair, unable to connect the laws of motion to their day-to-day dreams of the future.Studies
have shown that students are more motivated and interested when they are able to draw a straight line between their learning and its application to helping to solve real-world problems. This is especially true for girls
When we look at the problem of girls being under-represented in engineering programs across the country, one of the pain points we can identify is that girls are more likely to opt out of grade 12 physics
, a mandatory course for entry into post-secondary Engineering programs. Although there are systemic reasons for this, one of the easiest fixes is to make grade 11 physics curriculum more real-world solution focused. Read More...
September 30, 2021 Filed in: Articles
Robert Prior, ePublisher of OAPT Newsletter
Many of our students struggle with mastering the relationship between position-time graphs and velocity-time graphs. They may know that the velocity-time graph shows the slope of a position-time graph, or that the position-time graph shows the area under the velocity-time graph, but they have trouble telling if two graphs are related except by actually doing the calculations.
We all know that practice makes perfect, but drawing many graphs takes lots of time, and time is in short supply. This activity uses pre-drawn graphs so students spend time thinking rather than drawing. Read More...
June 23, 2021 Filed in: Articles
Eric Haller, Secondary Long Term Occasional Teacher, Peel District School Board
A couple of years ago I bought a bow and got into the sport of archery. To improve my accuracy at the range, I decided to invest in a laser rangefinder that could tell me the distance to my target, and its angle of elevation/depression. After using it for the first time, I discovered a third feature I was not aware of, the “Angle Intelligence™ Distance” (as it is referred to in the HALO OPTICS user’s manual). Interestingly, the rangefinder takes the angle of elevation/depression and the line-of-sight distance to the target into account, and calculates the adjusted distance to the target, as though I were instead shooting at a target across a perfectly horizontal field. Reading through the entire user’s manual, I couldn’t find any mention of what formula they used for the calculation, so I figured I would try working it out for myself. After a few hours of trying with a pen and paper, I discovered it was a lot more difficult of a problem than I had initially thought; so I turned to the internet. I eventually found the formula I was looking for; named the “rifleman’s rule.” The rule is fairly complicated to derive, however no part of the derivation requires anything beyond a grade 12 understanding of physics or math. This article will guide you through the derivation of the rifleman’s rule. You could work through it with your students, use this knowledge to help your school’s archery team, or even perhaps use it in the field yourself. Read More...
November 16, 2019 Filed in: Articles
Roberta Tevlin, OAPT Newsletter Editor, Teacher at Danforth CTI
One of the standard parts of an introductory physics course is a study of Newton’s Three Laws of Motion. They are part of the Ontario curriculum for grade 11 physics and most teachers would agree that they are essential. Chris Meyer has presented an improved way to teach the three laws of motion that will deepen student understanding: Teaching Forces I
and Teaching Forces II
In this article, I hope to reinforce Chris’ approach with a look at how the history of these three laws is wrongly presented. Read More...
October 28, 2019 Filed in: Articles
President, Ontario Association of Physics Teachers
Hybrid Teacher-Coach for Science, Toronto District School Board
Once classes have settled down and our students are trained (see the Quick Guide for Introduction Lessons
), we are now ready to focus on teaching some physics! The first unit often taught is motion, both in the grade 11 and 12 courses. Most teachers feel pretty confident with this unit, but I hope to share some tips that might help you out in a few tricky spots. Read on! Read More...
May 05, 2019 Filed in: Articles
Tim McCarthy, Teacher, St. Ignatius of Loyola Catholic Secondary School
Controlled experiments with three factors are a great way for physics students to practice identifying and testing factors that may affect a situation. They provide an excellent opportunity to practice the Scientific Investigation Skills found in Strand A. The students are provided with a situation, brainstorm possible factors that may affect the situation, reduce the list of factors to three that can be tested in the physics lab, develop hypotheses, design procedures to test the factors, test the factors, analyze the data, perform experimental error analysis, and draw conclusions on the effects the three factors have had on the original situation.
My struggle has been to find situations that easily fit this format and that also match the curriculum specific expectations. I have created one three-factor controlled experiment for each of the six units in my 12C physics course. The three-factor experiment in the first unit is used as assessment for learning (formative) to teach the students how to do a controlled experiment. The remaining five experiments are used as assessment of learning (summative). Simulations are used for some experiments as I do not have the necessary equipment to perform all them in the lab. Read More...
November 03, 2018 Filed in: Articles
Chris Meyer, President, Ontario Association of Physics Teachers
Here is a rich problem solving activity that I use when introducing the five equations of constant acceleration with my grade 11s.Goal:
I want to teach my students how to apply their new understanding to real physical situations and avoid plug’n’chug type questions. Read More...
October 19, 2018 Filed in: Articles
Eric Haller, Occasional Secondary School Teacher, Peel District School Board
In science, it’s always nice to be able to do a hands-on experiment. While there are many experiments you can do in class, there are some you can’t. Sometimes a particular experiment may require expensive equipment that you don’t have, may take too long to set up, may yield data that is too imprecise to analyze properly, or an experiment may be too dangerous for a classroom setting. At the latest annual OAPT conference Andrew Moffat showed us several websites with video libraries filled with experiments that I wouldn’t be able to recreate myself (skip to the end of this article for those links). To give you a taste of what kinds of videos are available, and how you might build a lesson around one of them for your students, I’d like to analyze one of my favourite videos from the collections. Read More...
September 17, 2017 Filed in: Articles
Nassi Rafiee, teacher Toronto DSB
Many grade 12 physics students plan to pursuit engineering in their post-secondary studies. Surprisingly, many lack a clear idea about the required skillset and what to expect in their next 4 years of education.
Last year I came up with the idea of having students design a mechanical pinball machine that demonstrates the mechanics concepts in grade 12. It was originally intended to focus on team building, engineering design process, physics calculations and writing skills, however as soon as I shared the idea with students, they got so excited that they formed their groups immediately and insisted that they wanted to build it too. Read More...
June 10, 2017 Filed in: Articles
Roberta Tevlin, Editor, OAPT Newsletter
Edited by Tim Langford
Projectile motion often involves a lot of mathematical problem-solving that is overly simplified and highly contrived. Football players do not stop to calculate the range before making a pass. Invading armies might want to make calculations for siege weapons, but these tend to be too complicated (trebuchets) or involve too much energy loss (catapults). Guess and check, was probably the preferred technique. Fortunately there is a cheap and reliable projectile launcher that you can use to show that physics works. Your students will be able to use it to hit a target on their first shot by using calculations for conservation of energy and projectile motion. Read More...
April 29, 2017 Filed in: Articles
A Practical Experiment For Learning Kinematics and Other STEM Concepts
Dr. Theresa Stotesbury, Research and Product Development, Trent University
I am part of a research group out of Trent University (Peterborough, Ontario) that has developed a teaching kit that provides a 60-minute problem-based experiment that is suitable for high school science students. The activity connects forensic science and kinematics through the analysis of blood spatter. I will be presenting the kit at the OAPT conference at 9:30 on Friday May 12th. Read More...
March 17, 2017 Filed in: Articles
Dave Doucette, OAPT Vice-President
While teaching uniform circular motion in high school, I struggled with developing the ac = v2
relationship in an intuitive and cognitively meaningful way. Geometric arguments do not resonate with students. They accept on faith but often with little interest or insight. Here is an approach that may do a better job. Read More...
January 20, 2017 Filed in: Articles
Ryan Thompson, OAPT Treasurer, Physics Teacher Newmarket HS
When the Growing Success
document came out in Ontario, the terms “Assessment as, for and of learning” were introduced. Even after teaching for 13 years, I still have to pause and stare into space as I try to differentiate between the three types. Time dilation is easier than that!
I believe in timely feedback and having direct involvement in each student’s success but I am also managing a schedule that is very limited on time (time dilation again!). As a result, I try to do what I can in the classroom
This article will be about one technique that helps me reconcile the Growing Success
document’s expectations, my own philosophy of teaching and limited time in the school day. This tool is called The Check Up and it helps the teacher get quick feedback about your past lesson. Read More...
December 11, 2016 Filed in: Articles
John Berrigan, Teacher Oakville Trafalger H.S.
In the previous article
we found the main factors that determine the thrust of a rocket engine. We rearranged the formula and determined the Impulse of the formula for rockets.
With Elon Musk discussing his Mars rocket last week, http://www.spacex.com/mars
, now is a good time to discuss how Impulse can be used to eventually determine the efficiency of a rocket engine. Read More...
October 02, 2016 Filed in: Articles
John Berrigan, Teacher Oakville Trafalger H.S.
In the previous article
we learnt how to find the largest possible delta-V that a rocket can experience. In this article, we are going to find the thrust of a rocket by using the fundamentals of conservation of momentum. This will be similar to what we did in the last article, however this time we will use variables instead specific masses and velocities. Furthermore, the cart is now a rocket, as this is rocket science! Read More...
September 02, 2016 Filed in: Articles
Michel Enns, Teacher Runnymede CI
I have been frustrated with gravitation simulators over the years because they stop working when the computers are updated. To avoid this, I have made one that is browser-based and will run on any device. You can find it at www3.sympatico.ca/michael.enns
. One non-standard thing that it can do is simulate the formation of a solar system with a thousand random masses. Read More...
February 20, 2016 Filed in: Demo Corner
Ryan Thompson, OAPT Treasurer, Physics Teacher, Newmarket HS
I purchased this little magnetic moon rover at Masterminds for $6 a few years ago because I thought it was cool. I didn’t have any specific ideas on how to utilize it until a few years later when I was teaching the famous river question to students. You know how it goes: Alice is crossing a river that has a velocity with respect to the shore of 4 m/s [East] and Alice swims with a velocity of 3 m/s [South] with respect to the water. If the river is 60 m wide, how long does it take Alice to get to the other side? The concept that is hard for students to reconcile is that even though Alice is being pushed to the right from the shores frame of reference, the amount of time to get to the other side is independent of the river’s velocity. This is when I had a Eureka moment. I grabbed the moon rover and put it on our whiteboard. I then wound it up and let it go south, just like Alice would. Read More...
January 01, 2000 Filed in: Demo Corner
Ed van den Berg and Rosea van den Berg, University of San Carlos, Talamban Campus, Cebu City, Philippines
This article was excerpted (with the authors’s permission) from a longer article in
The Physics Teacher (Sept. 1998, p.356-8).
What can we do to have clear and exciting lessons without a great amount of demonstration apparatus and hours of preparation each day? We present here a collection of small and quick demos that require no equipment beyond what is present in a classroom (chalk, chairs, students, books, paper, backpacks and their contents). Some are to prove something, but most are to illustrate, visualize, or simulate. These basic and well-tried ideas will stimulate students and revive the instructor who has spent a late night checking student papers. Have fun! Read More...