STEM Club News: Dec. 2018
Posted on 12/21/2018
Students in STEM club tried to get to the bottom of an important scientific question: when Spider-Man uses his web to swing through the city, is that web stretchy, like a rubber band, or it is more like a rope? The kids knew the answer right away: it’s stretchy, like a rubber band!
Rubber bands are really cool, not just because you can use them to explode watermelons but also because they let us teach the kids about a specific kind of potential energy*, called elastic potential energy – it’s the reason that a stretched rubber band returns to its original, unstretched state.
Students explored these concepts by building their own scale out of cardboard, brass paper fasteners, paper clips, and a rubber band. They then took objects with known masses to calibrate their scale.
Aroon (5th grade) noticed that the distance between the 0, 50, 100, 200, and 300 (gram) marks weren’t spaced out like he expected: the distance between the 0 mark and the 100 mark were not the same as the distance between the 100 and 200 marks or the 200 and 300 marks. Great scientific thinking! That’s because rubber bands stretch in what is called a nonlinear fashion – for this reason, our scale is less accurate the more the rubber band is stretched.
Parent Josh reminded students that kinetic energy is the energy of motion, like a ball falling out of a window and potential energy is the energy that the ball has, when it is 10 or 30 or 100 feet off the ground, before you let it go.