LHS 'Mythbusters' get physics lesson at the drag strip

LACONIA — The Laconia High School applied physics – also known as "Mythbusters" – class has been learning its latest lesson at a 20-meter long drag strip set up in a corridor outside a classroom. While students challenge each other for  bragging rights, they're also learning about mass, acceleration, thrust and friction.
Teacher Jo-Ann Gilbert gave each student in the class a wedge-shaped piece of wood, measuring two inches wide, three inches tall and 13 inches long, and allowed the students to come up with their own design. The only stipulation was that their dragster, which are propelled by tiny canisters of compressed carbon dioxide, have four plastic wheels and weigh no less than 50 grams (the blocks started off at 256 grams). Then, the students took their dragsters to the wind tunnel in the Huot Center's manufacturing classroom for fine tuning.
Yesterday, students in the two applied physics class faced off, head to head, to see whose dragster was fastest. In the morning section of the class, Zach Harper left his classmates in his dust, racing the 20 meters in 2.65 seconds.
Harper's car followed the "less is more" philosophy of design, shortening his wood block considerably and sanding away all but about a quarter of the car's starting weight. In the later class, Erik Parker, the lone sophomore in a class of upperclassmen, took the top slot. Although his time was approximate with Harper's, he approached the problem with a different strategy, ending up with a dragster about twice the weight of Harper's.
"I was trying to take off as much wood as I could," said Parker, though he said he wanted to keep the car's wheelbase as long as possible. "I felt it would help maximize my stability," a quality his design proved when tested for aerodynamics. "It did fairly well in the wind tunnel."
As Gilbert explained, the dragsters that performed best weren't necessarily the lightest, but those which exhibited the least rotational friction between the wheels and the bodies of the cars. After yesterday's qualifying races, Parker said he was going to try and improve the efficiency of his wheels. The first round of races were propelled by 4 gram cartridges of compressed gas, the championship round will feature the use of 8 gram cartridges.
Whether or not Parker wins the final round of drag races, he said he's enjoying the experiment. He said, "I thought it was a very good lesson. I learned a lot about mass, drag coefficient and acceleration."

Students in Laconia High School's applied science class built and raced dragsters to learn about friction, drag and acceleration. On Monday, the fastest cars from each of the two sections will race head-to-head for bragging rights. Erik Parker, shown here, standing, built the fastest car in his class. (Laconia Daily Sun photo/Adam Drapcho)

Kirsten Harris, a senior at Laconia High School and student in the applied science class, tests the aerodynamic properties of her dragster "Cobra" using a wind tunnel. (Laconia Daily Sun photo/Adam Drapcho)