Science Journey: Playing with Toys

Standing on a skateboard with a medicine ball in his hand, Zach Tobin asks what will happen if he throws the ball. He does so and proceeds to glide shakily in the opposition direction. "Equal and opposite forces, right?" he says. The scene might seem like something you would see on TikTok, but in fact is one of many physics demos that Tobin has catalogued as part of his job at Caltech. The demos cover many basic principles such as Newton's laws of motion, the relationship between electrical currents and magnetic fields, and the conductance of electricity by air. The demos also include props such as stuffed monkeys, lava lamps, and tubes of flames.

The collection includes more than 250 demos, more than 200 of which are catalogued on video and available online. Tobin notes he began to put even more demos on video due to the COVID-19 pandemic and resulting shift to online learning.

About the Speaker

Zach Tobin is the Physics Lecture Hall Manager. His career path may have stemmed from inspiration he received in college. He recalls the time a teacher placed a cinder block on their hand and "started hammering it to death." Luckily, the block was massive enough to absorb all the energy and not cause damage to the teacher's hand, as you can see here in a similar demo by Tobin. That same teacher also ate chalk, he recalls.

Later, Tobin went to Caltech for graduate school and studied in the lab of Caltech Professor of Applied Physics Paul Bellan. He left after earning a master's degree in physics.

Tobin then worked at Pasadena High School, where he developed computer and math classes, and taught Android app development and robotics. But he said that job "wasn't really for me" either.

Now, Tobin is happy to have found his way back to Caltech. Outside of his job responsibilities, he also builds props for Caltech theater productions. He helped create a giant, carnivorous plant for a production of Little Shop of Horrors, and even made Klingon weapons called bat'leths for a raucous production of Boldly Go, a musical parody based on the television show Star Trek.

Theater, he says, is not that different from science demos. "You need something interesting to look at or most people aren't going to care."

Series Cosponsor: Caltech Employees Federal Credit Union