# Erik Thogersen

Erik Thogersen
Project Director

Right out of college, Erik caught a lucky break as an intern prototyping some of the few interactive exhibits at the Smithsonian’s Air and Space Museum. After a few detours to build robotic animals for Hollywood and study plasma physics, he landed at the Exploratorium in 1996 and immediately found his niche, right at the intersection of science and human interaction design. He discovered a deep passion for noticing how the details of exhibit designs do and don’t work for visitors. Over the years, he has designed a wide variety of exhibits on topics ranging from the human mind to electricity to motion to mathematics. He loves simple designs with rich interactions. Erik helped curate the museum’s Time, Motion, and Math sections and leads its Core Physics and Perception Initiative.

Going further

If you look closely, you may notice a crisscross pattern of wire underneath the largest chair. Doubling the dimensions of a normal chair to get the largest chair means increasing its weight by a factor of eight. This chair is so heavy that the added wires are necessary to keep it from collapsing—visible proof of the impact of “scaling up.”

This exhibit helps explain why ants don’t grow to be giant sized, as in horror sci-films. Scaled up to colossal proportions, a giant ant would have legs too skinny to support itself. There’d be no need to squash it—it would collapse under its own weight.

Going further

For your ear to hear a reflected sound as a distinct echo, the delay between the initial sound and the arrival of the reflected sound must be greater than about a tenth of a second. Since sound travels at roughly 340 meters (1,100 feet) per second, a sound-reflecting surface has to be at least 17 meters (56 feet) away to produce an echo.

Challenge: Our Echo Tube is about 60 meters (200 feet) long. Can you use the speed of sound (340 meters per second) to estimate the expected time delay between a sound and its echo? Photo © 2013 Bruce Damonte, all rights reserved. (click to image to enlarge)

An Echo Tube doesn’t need to be straight to work—sound travels by bouncing between the walls of the tube, be it straight or curly. (click image to enlarge)

Related Exhibits

Going further

If you look closely, you may notice a crisscross pattern of wire underneath the largest chair. Doubling the dimensions of a normal chair to get the largest chair means increasing its weight by a factor of eight. This chair is so heavy that the added wires are necessary to keep it from collapsing—visible proof of the impact of “scaling up.”

This exhibit helps explain why ants don’t grow to be giant sized, as in horror sci-films. Scaled up to colossal proportions, a giant ant would have legs too skinny to support itself. There’d be no need to squash it—it would collapse under its own weight.

Going further

For your ear to hear a reflected sound as a distinct echo, the delay between the initial sound and the arrival of the reflected sound must be greater than about a tenth of a second. Since sound travels at roughly 340 meters (1,100 feet) per second, a sound-reflecting surface has to be at least 17 meters (56 feet) away to produce an echo.

Challenge: Our Echo Tube is about 60 meters (200 feet) long. Can you use the speed of sound (340 meters per second) to estimate the expected time delay between a sound and its echo? Photo © 2013 Bruce Damonte, all rights reserved. (click to image to enlarge)

An Echo Tube doesn’t need to be straight to work—sound travels by bouncing between the walls of the tube, be it straight or curly. (click image to enlarge)

Related Exhibits