Life-Size Lessons

Physics students build giant Newton's Cradle

Physics students build giant Newton’s Cradle

A Newton’s cradle is a great way to demonstrate the laws of physics on a desk or a bookshelf. Lift one ball as a pendulum, let it fall and strike a row of balls that hang together, and the ball on the other end will bounce away while the others remain still.

Randolph College’s Society of Physics Students recently brought that concept to life on a large scale. They built a Newton’s cradle with two-by-fours and bowling balls to provide a fun way to practice engineering skills and get people interested in physics.

“I like to do an engineering project every year,” said Peter Sheldon, a physics professor and the club’s advisor. “It’s another way to bring together the Society of Physics Students and the campus community in a really constructive way.”

Sheldon said these build projects, as well as the annual Science Festival, are among the reasons Randolph’s Society of Physics Students chapter is regularly recognized for its great work, winning an “Outstanding Chapter” award from the national society for eight out of the last nine years.

“We look for fun projects to do that we can use for outreach,” he added. “It’s usually something big and ostentatious.”

Sheldon had seen giant Newton’s cradles before, so he challenged his students to build one themselves. Main Street Lanes in Farmville donated five used bowling balls. Students built a frame out of wood, drilled holes in the balls, and suspended them from the frame with wires.

Hart Gillespie ’15 said these build projects give students a way to apply what they learn in the classroom. “While theory is all fine and good, physics is ultimately done in experiments,” he said. “These build projects are like physics experiments: you build something, you see whether it works or not, and if it doesn’t work, you find a creative solution to the problem and make it work.”