Motion- the first bridge between mathematics and physics. My Year 10 classes and I finished Term 1 off by beginning our exploration into the physical phenomena of motion. In a school with a high English as An Additional Language or Dialect (EAL/D) student population such as ours, I find it extremely satisfying to be able to use mathematics, the universal language of the universe, to communicate our observations and ideas in the classroom.
In order to describe the physical world, students need to be able to understand the mathematics behind it. Our topic began by revisiting distance, speed and time calculations through the classic DST triangle (as seen in the image). BBC has a short tutorial on how to use the triangle. I found that students prefer using a visual aid to help in their calculations. It eliminates the barrier of not remembering the formulas.
Experiment 1: Measure your speed
Now that students are familiar with the calculations, students explore how these equations are relevant to real life. In one lesson, I took the Year 10 students outside to find out the speed of their walk, jog and run. I pounce at any opportunity for students to be physically active in their learning, as it is engaging for all and will wear the students out (No complaints on this side :P). I lay a fluorescent tap measure at 20 metres in length on the grass. Students were to use the stopwatches on their phone to time how long it took for them to complete the track at various paces, with 3 repetitions for each pace for reliability. After they finished, they could sit on the bench and calculate their average time taken to complete 20 metres at each pace and use it to calculate their average speed using speed = distance/time.
Experiment 2: Toilet Paper Practical
A colleague of mine came up with this experiment as a prerequisite to using ticker timers (Thanks Ping!). The experiment is simply a ticker timer on a larger scale and enables students to visualise and act out how the ticker timer works. The set up of the toilet paper practical is in the image above. This experiment requires 3 people per group.
Person 1 (Dispenser): Holds the toilet toll, which is fed through a rod (or equivalent).
Person 2 (Marker): Student holding the marker and timer.
Person 3 (Mover): Student who pulls the toilet paper whilst walking back.
In this experiment, the marker makes a dot on the toilet paper every second for 10 seconds, whilst the mover pulls the toilet paper back in three different motions (slow, fast and accelerating). Students use the marks they obtain on the toilet paper to calculate the speed of the the mover, using the idea that the dots were created one second apart e.g. speed (m/s) = 20 metres / ? seconds.
In this practical, students enjoyed running with toilet paper.
Experiment 3: Ticker Timer
An explanation of the ticker timer can be found in this link. Essentially, the ticker timer creates a dot on the ticker tape every 0.02 seconds or 50 times a second. We can use the distance between the dots to calculate speed. Students get confused with the idea that the dots are created every 0.02 seconds. Referring the students back to the toilet paper practical helps them to understand that the dots were placed intentionally at this time interval and is essential for our speed calculations.
Overall, the introduction to Yr 10 physics has been hands on and has enabled students to actively learn and test the concepts of motion. This approach has made the teaching and learning enjoyable on both ends.