light ON

Long weekends are the best! But now it’s Monday night and I have to do all of my homework… I didn’t take much pics this weekend so I thought about what I’d blog as I was getting ready for dinner. Then suddenly, as I sat down, a light went off both in and above my head! My sister had turned on the light above our dining table—reminding me of variable resistors and light dimmers. The light switch for that particular light is a circular knob that you push to turn on/off and turn to adjust the brightness; however there are light dimmer switches can also be used by sliding a lever. In the case of my light, a simple method was devised to adjust light levels: variable resistors. A typical resistor is made of a material that doesn't conduct electrical current well. A variable resistor is made from a resistive material comprised of a stationary and a moving contact arm. In the second picture, I captured the knob and drew its basic components (sorry it's messy..i drew it in on my camera). The total resistance of the resistor in this case is varied by adjusting the distance the current has to flow through the resistive material. In my illustration, the moving contact arm is touching the bottom right portion of the resistor. By turning the knob to the left, the contact arm moves in the counter-clockwise direction; thus decreasing the distance the charge has to travel. So when this occurs, the contact arm is to the left and the charge only has to travel through a small amount of resistive material—brighter light! Similarly, when the contact arm is in a position similar to the one I drew, the light emitted is dimmer because the charge has to move through more resistive material. Physics is so illuminating!

SHOCKing!

Ahh this weekend was exciting! Even though the Cardinals lost (they had it!!), and BJ Penn, well..., it was my bday and there was an extra long Office :D Even thought there was a ton of physics involved, I didn’t get a chance to take any pictures of the fight or game. So, I was thinking of what we were learning in class and dug up this picture from this past spring break. Here’s Remi and me on our uber epic trip, waiting for the Bellagio water show to start. These shows never disappoint—one of them was even set to Andrea Bocelli’s, “Time to Say Goodbye!” And although we thought Vegas wasn’t going to be that fun, since our parents planned that part of the trip..(and we were waiting for Disneyland), we got to see “Love,” and experience physics firsthand. As we learned in class, objects usually tend to be neutral. We included, like to remain in a neutral state, but sometimes charge imbalances do occur. Since objects like to be in neutral states, when they lose their balance of protons and electrons, they want to either lose or gain electrons to return to neutrality. Objects reduce their charge imbalances immediately when their electrons are given the freedom to flow. Getting shocked is an example of this occurance. Here in Hawaii, moisture in the air (caused by our consistently humid climate) reduces charge imbalances on its own so we rarely experience shocks. In places with drier climates such as Las Vegas, however, shocks are common. This difference in weather therefore made us subject to more severe static shocks than the ones felt back at home. One place static electricity was eveident was at our hotel room door. I’ve experienced shocks in Vegas from opening doors before, but none quite as “big” as one of the ones I recieved early one morning. On our last night in Vegas, we stayed out later than usual to take in our last sights of the city. The next morning, I had the hardest time waking up because I was tired and the cool weather just made me want to stay in bed! But I slowly got ready. Dragging myself around the room, I got my stuff together and headed for the door. When I reached out to turn the handle, I felt a shock surge through my body! I realize now that the magnitude of the shock was so great because I was accumulating electrons from the floor each time I dragged my foot on the carpet. By the time I reached the door, my body had a negative charge and wanted to return back to a neutral state. So when I finally came in contact with the handle, the electrons in my body rushed towards the neutral doorknob, resulting in a shock. Static electricity was also evident in my hair. Especially when I brushed it in the mornings, I could “feel” my hairs repelling each other, and see it in the mirror. This effect came from the electrons I received from the carpet as well. So, next time in Vegas, I’m gonna use all of this knowledge of charge to create a monster shock for my sister! ;)