BROCKWAY – Seventh-grade students at Brockway Area Junior Senior High School are racing cars for science.
The students in Matt Oknefski’s class are developing small race cars to see if they can figure out how basic forces, like gravity and friction, can impact an object’s movement.
Oknefski usually has his juniors and seniors build balloon-powered cars to race down the hallways, but this project was a new experiment.
“I’ve never done this one before,” Oknefski said. “I asked the general science teacher for fundamental science concepts that the students need a little more background knowledge in, and basic forces like gravity and friction came up. I teach a lot of the basic forces, but I never got into gravitational energy in my class. We’re taking that another step.”
Gravity is a well-understood force, but potential energy is not. To start, students have to design and build cars that cannot be more than 12 inches long. Then, Oknefski gives his students a starting line on a ramp that he builds in the hallway. The starting line is where the discussion of potential energy comes in.
“If they come back off the starting line, the car does better, because it has more potential energy,” he said. “I let them explore the ramp and help them think about what brings their cars forward.”
The goal is to beat Oknefski’s car in a race.
Tommy Ceriani and his team of Logan Salizzoni and Diamond Thompson said the project is more difficult than throwing a car onto a ramp.
“We have to get it to go as far down the hallway as possible,” Ceriani said. “It can’t be a bought model car or toy car. We have to build them ourselves.”
The competition was a major factor in the students’ involvement.
“We have to build it and beat Mr. O,” Salizzoni said. “We have to be the best in the grade.”
Weight is a factor in building the cars, which Trinity Bish, Rayvin Clinger, and Brianna Forsythe discovered.
“We hypothesized that if we added more weight onto the car, it would go further down the hall,” Clinger said.
The designs varied, as did the materials used. Oknefski gave them general guidelines to follow, but the students developed their designs based on resources they thought would give them the maximum potential of winning.
“We used straws and old DVDs for the wheels, and we painted the outside black,” Kellyece Joseph said. “Building the car has taken us most of the week.”
Oknefski said the students are working to find the “Goldilocks Zone” for the weight. If the car is too heavy, it puts too much friction on the wheels. If it is too light, the car will not have enough weight to be fast.
“Yes, their goal is to beat my car, but, really, I want them to explain the physics why their car worked or didn’t work, and how to improve it,” he said. “If the car doesn’t work, that’s a learning experience. They just learn how not to make a car. Every car works to an extent, but some will go six feet and others will go 60.”
Oknefski said that the reward for beating his car is that he will pay for lunch for the students.
“They can order from wherever they want in town and I’ll pay for it,” he said. “The amount of work they have to put in to beat me is worth me buying a group lunch.”
Between this project and the balloon car project, Oknefski has yet to buy lunch for anyone. However, he would not give away his secret.
“I know how to minimize friction on my car,” was all he said.
For the students, the competition was worth the experience, even without lunch. Zoe Puhala said that her plastic straw and bottle cap car needed work but was driving well.
“This was a hard project, but it was fun to find out how far your car would travel at the end,” Puhala said.