Can you catch the properties of a wave using slo motion?
Sure high brow universities and high schools have the equipment to do such things. What about a middle school? Building oscillators in science today and students were faced with a problem. How to measure one cycle's worth of motion.
My oldster thinking thought stopwatch to find the wave's period.
Their youngster thinking thought use the cellphone's camera in slow motion!
Here's an example of what they photographed. This is a screenshot of a video.
You'll have to look very closely to see the wave as it hits the bottom of its cycle in the photo.
Once we realized we could see this, then we had to figure out how we measure what was happening.
My challenge had been to measure the original period of your oscillator and then figure out a way to increase it and decrease it.
Here's the tweet we sent out as students came to understand how to do this. Fortunately I still had some usefulness.....if we knew the rate of frames that the video captured and they counted how many it took to go from the top to the bottom, they could then calculate the time it took to do one complete cycle by doubling it. We're well on our way to being able to answer what kinds of patterns does a wave have which will help us understand how to build mathematical models of waves. Hurray for NGSS asking us to undertake this task (MS PS4)
Cracks me up. We did problems like this in the textbook. Now we were living the problems in a real life setting. Here's the tweet we sent out as we realized how to gather this data.
Ss solved prb of no photo gates. Took vid with phone, slowly counted frames & could accurately find waves period. pic.twitter.com/8iYRZJYr6t— ratzelster (@ratzelster) April 28, 2015
Even though we're not equipped with fancy science classroom equipment, we still figured out how to do it.
Gotta feel like this is a good example of co-creating knowledge with students. I had some of the pieces of knowledge and they had others. Together we had a solution.
My 8th graders can catch a wave and define it's properties.