Russell's Blog

I met up with Gabe, Eric, Becky and Steve and we went over to Para Los Niños, where we did a 40 minute demonstration of static and induced magnetic fields. Everyone seemed to have a great time. Instead of taking pictures myself, I handed my camera over to the regular teacher, who took some great shots.

In this demonstration, we used a piece of high-temperature superconductor glued to the bottom of a Styrafoam cup. These superconductors work at liquid nitrogen temperatures, so Eric brought a dewar of it from UCLA. Once the superconductor is cooled down, the cup easily levitates above and floats up and down special track of strong magnets. The magnets on the ends are inverted, so they act as little magnetic bumpers. The cup happily floats back and forth until the liquid nitrogen boils off.

The kids had a great time pushing it up and down the track. It's a very compelling demonstration, and one I've never had the chance to see before.

We also brought a large electromagnet designed to run off of 120 VAC. We used it to shoot aluminum and copper rings into the air (rail gun!!). We also had these nifty little magnetic probes -- basically, a tiny bar magnet on two-axis gimbals -- that are supposed to be used to show the orientation of a magnetic field. The idea is that you put them near a magnet and move them to different positions, and the bar magnet will always be free to rotate into alignment with the field. I figured that they would do something more interesting in an alternating magnetic field, and indeed, they made fantastic impromptu AC motors.

We had a few other cool demonstrations, too. We watched some strong magnets float down copper and aluminum pipes, dragged by the magnetic fields of the image currents in the metal pipes.

As usual, the kids were fantastic. LA has heartbreaking problems with its schools, but this place gives me some hope that those problems can be fixed fairly rapidly. The kids in this program have a lot stacked against them; poverty, no English-speakers at home, foster care, or often all three at once. With all the administrative problems the LAUSD has, it can barely provide adequate education for kids who everything going for them. These kids would normally be tossed aside as a lost cause.

Lost cause indeed. One of the kids told us that, "UCLA is my dream school." Steve told him that he'd look for him in freshman physics in a couple of years. When you see how they act in the classroom, you'd never question thier chances. But then I remember what they have in store for them; there is no program like this beyond the primary school level. Plus, the UC budget hasn't done much to increase the number of scholarships, and fees keep going up. Even middle class families are starting to get priced out of a public university education. I hope that kid gets his wish, but I worry that he'll be cheated out of it.