Graphing Quadratic Equations: Pendulums

Pendulum
It’s best if students get to experience collecting actual real world data and seeing that data actually forming into the quadratic model. A worksheet filled with numbers that claims to be “from a science experiment” or “real world data” is not. To me, real world is something students can gather themselves or experiment with.

One experiment that you could use is the pendulum experiment. This is a classic physics lab that demonstrates how length affects the period of a pendulum. There are 3 options:

1) The best option is an actual, hands on experiment. Go here for tips on how to set up the experiment. All you need is some string (sturdy-ish), a weighted object (unbreakable, preferably), something heavy (like a stack of books, or someone could hold/sit on it) and a stopwatch. The gym should have stopwatches, or there are online timers. Your science department might even have actual pendulums.

2) A second option is to use a computer simulation of a swinging pendulum. The students can collect their data in a computer lab or with class laptops. The worksheet on Algebrafunsheets is a worksheet for this online version.

3) A final option is that the teacher could perform either the hands on or the computer model experiment in front of the class, soliciting student participation, and gather the data together as a class. Probably the least effective method.

What students should discover is that their data will curve in the typical quadratic model (you’ll need to set the x-axis as time and y-axis as length if you want to keep the “u” shape Algebra 1 students are typically asked to graph).

A great way to finish the graphing quadratic section is with this brief film “Parabola” by Radiolab. 4 minutes long. (Most are not true parabolas, but I love the into).