Monday, February 28, 2011

Wiring

I live in a old house from the 70's in Hawaii Kai, and I guess when housing was being built back then there were fewer standards that needed to be met. I say this because the genius that wired all of the bedrooms in my house connected them to the fuse box in a series circuit rather than a parallel circuit. While the electrician attempted to explain this to my family (it is a difficult concept to understand, house wiring) this essentially means that there is one path for the current to flow along and goes from one outlet, or resistor, to the next with no alternative route. In other words, if one of the outlets burns out, they all go out. My family learned this the hard way when we had three air conditioners on in the bedrooms at the same time and the power went out because there was too much voltage required, a very high current, low resistance, and overheating. In order to rewire the house properly we learned that we would pretty much have to tear down half of the house so for now, we fixed the burned outlet and carefully watch what is turned on at the same time to prevent this from happening again.


The oulet in my room that burned out because of the electrical overload:

Thursday, February 3, 2011

This weekend was my Aunty's 50th Birthday, so to celebrate our family went to her favorite restaurant for dinner. We got there early to decorate the private party room, and it was the job of my cousins and I to strategically place all of the balloons around the room. However, after our physics lab in which we observed static friction after charging a balloon by rubbing it against someones head, I began to chase my little cousin around to show him how cool repelling balloons are.

When I rubbed the balloon against Roman's hair, the balloon picked up extra electrons and had a negative charge because it was charged by friction. Holding it near something neutral, like his arm, polarized the hairs on his arm (positive charges moved closer to the balloon because opposites attract) due to induction because the balloon had a negative charge in one area. The static charge built up and each of the hairs had a positive charge near the balloon, and things with the same charge repel each other. That is why the hair on his arm was standing up - the hairs wanted to get as far away as possible from the other hairs that had the same charge, but closer to the balloon that had the opposite charge. The same concept applied when I rubbed a second balloon on Roman's hair, so that it also became negatively charged, and held it near the other balloon. Because in the spots that were closest together both balloons had a negative charge, the balloons were trying to repel each other because the electrons were trying to get as far away from the other electrons as possible.

Roman thought these physics "tricks" were pretty cool and that I was some kind of magician, but really I'm just a physics student who learned that its not that hard to impress a 3 year old :)

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