Everyone is making the joke about how many so-and-so do you need to change a lightbulb, but no one's asking it for real. But I wonder what it is: Are there places where you can't change a lightbulb as one person, because of its location or because of the shape of the bulb? What about spacecrafts, like the ISS? Does a single person change the light bulb on it? I am really tuned for what you may find out.
In 2016, they started changing all the fluorescent lights on the ISS for LED panels. Bec contacted the principal investigator in a study on lighting's effects on astronauts, Steven Lockley from Harvard, who confirmed the lights are still being changed. Because this inquiry was inconclusive, Bec contacted astronaut Tim Peake, who was there while the bulbs were being changed out.
There's a lighthouse in Florida that changes its own bulb. Bec contacted the Split Point lighthouse, who in 2015 changed their light bulbs for LEDS, which took two people. It also takes two people to change the light bulbs on top of an aerial tower. Changing the spotlights on the Eiffel Tower takes 43 technicians.
The largest light bulb might've been created for an art installation in Tulsa, Oklahoma. It took 50 people to install, but you can't change it because there's only one of it. It's powered by LEDs, which take only one person to change.
Eventually, Bec heard back from Tim Peake. While not a light bulb, a light assembly took only one person to change.
A ding by the audience
How big should my trebuchet be if I wanted to use it to throw projectiles faster than the speed of sound? Forget about the material problems here, assume that the machine itself would be able to cope. How far would it shoot? Assume ideal situation with no drag. Could we shoot into space? Would this trebuchet be the first environmentally friendly space force?
To go to space, you need to launch it at roughly 11'000 m/s, which is Mach 32 (32 times the speed of sound in air).
Since they couldn't bring a trebuchet, Matt brings on-stage a "kinetic energy demonstration device" consisting of two brooms and two 5 kg weights. Because the APS merch didn't arrive in time, they're launching bluedot and Numberphile T-shirts into the audience that Bec turned into APS merch.
To launch a shirt into space, you'd only need a 940 ton counterweight a metre off the ground. Whether this is environmentally friendly depends on where the energy to lift the counterweight came from.
A ding by the audience
Tomorrow, Matt will be signing copies of Bec's Horror Heights books, and Bec will be signing copies of Matt's Humble Pi book. They will also be selling T-shirts.