happy holidays with physics

While I was watching TV, I glanced over at the Christmas tree my mom decorated. Because of the huge mess Christmas tree make, my family has an artificial tree. The tree originally came with lights already on the tree. After a few years, some of the lights stopped working. I recently realized that this was due to a string of Christmas lights that was arranged in a series circuit. The result: when one bulb goes out, the others on the string stop working as well. My mom replaced the lights with a new string that's arranged in a parallel circuit so that if one of the bulbs go out, she won't have to replace all the lights again.

rear view mirrors

On Friday, my friends and I went to the Aloha Stadium to watch Iolani's football team compete against Radford for the div II state title. Iolani beat Radford 35-20. After the game, we decided to go to Pearlridge to get dinner and catch a movie. Matt was driving in front of me and Shantha while we were leaving the stadium. While we were stuck in traffic, we remembered that if Matt looked into his rear view mirror, we would be able to make eye contact with him, and we would both be able to see each other. We learned this in physics in the past week and this occurs because of the angle of incidence and the angle of reflection. Shantha and I began to jump around in the car, and waved our arms to try to get Matts as a good driver should, he kept his eyes on the road, and didn't see us in his rear view mirror.

Red Roses

This week I didn't really notice very much physics around me. After completing the worksheet for the weekened however, I realized that there was physics right on the dining room table. On monday it was my mom's birthday, so my dad bought her a bouquet of roses. The roses were a very vibrant red. This past week, I learned that they are red because it reflects red light. White light consists of red, blue and green light combined together. When the white light shines on the rose, the flower absorbs the green and blue light, reflecting the red light, which is why the roses look red.

Metal Detectors

Lately we have been learning a lot about magnets. On the past test, we were asked how metal detectors work. Although I am not completely sure, I know that it has something to do with magnets. Metal detectors use electromagnetic induction to detect metal that passes through them. Inside the metal detector is a coil. A current is passed through that coil to create an alternating electromagnetic field. When metal passes through the detector an alternating magnetic field is formed around that metal. Another coil detects the field of the metal that passes through the detector. After thinking about how metal detectors work, I thought about this past summer when I visited Vietnam. We caught many flights around the country but before returning to Hawaii, we stopped off in Japan. One of my friends decided to buy Cuban Cigars as a gift for his dad since you can't get them legally in the U.S. He bought them at the airport he had to carry them on. He left them in his pocket when we went passed security and the metal detector beeped. This was an indication that there was metal in the packaging that set of the alarm. Now I have a better idea how exactly that metal triggered the alarm.

Magnetized keys

A few weekends ago, we went to the Big Island and stayed at KMC for senior camp. We did a lot of fun activities, played games and got to hang out with friends. We also had to practice our class cheer for the cheerfest which we ended up taking first in. During our free time, my friends and I went to the general store to pick up some energy drinks so I grabbed my phone, credit card and room key and shoved them all in my pocket before running out the door. We visited our friends who were in a different room before going back to ours. When we got back to the room, I took out my key but it wouldn't unlock the door. I must have tried 20 times until I finally gave up. I assumed my room key got mixed up with one of my friends from a different room, but Sachi asked me if I had my room key by my cell phone. When I told her I did, she said that there are magnets in cell phones that can demagnatize the room key.

Concept physics so far...

This past week has been very exciting. Homecoming was lots of fun. Concept physics has been kind of interesting so far. I like that the class is very hands on and that the concepts are demonstrated in several ways including everyday analogies. This really helps me to better understand the concepts because sometimes only reading the book confuses me. I thought that the cicut projects were esspecially helpful. Although some of the projects really confused me, it was good that we could think of something personal that related to the way a circut works. That definitely made it a lot easier to understand. Other than that, this upcoming quarter, I would really like to improve on grasping the concepts. A lot of times, I just fill out the homework questions to get it done with. My goal is to be more thorough and hopefully that will reflect upon my tests and quizes.

Physics in the Ala Wai

This week, I didn't really notice anything that had to do with the physics we've been learning recently. Luckily, when I went for a run earlier this week, I did notice that there was more than just trash in the Ala Wai; there was some physics in there as well. When I looked over the bridge and into the water, I saw two ducks swimming together. Behind the ducks was a bow wave. Bow waves are waves that are "v" shaped and can be formed by ducks, like what I saw, or even boats and ships.

Static Electricity

We've recently been learning about static electricity. There are three different ways for an object to obtain a charge. The first is by friction. This occurs when two materials rub together and one of the materials wants to hold elctrons more than the other. The second way to charge and object is by contact. The is when there is one charged object and one neutral object. The neutral object obtains some charge when the charged object comes into contact with the neutral one. Charging by contact only occurs with conductors, not insulators. The third way is charging by induction. A neutral object can become charged without having physical contact with a charged object. As we learned, static electricity is found in dry places. After doing some laundry, i noticed that my clothes stuck to each other and I could sometimes hear the static electricity when i pulled them apart. Static electricity takes place in the dryer not only because its a dry place, but also because of the friction. The clothes become charged because of the friction.

Yellow Waves

This summer, I went to Arizona where we did a lot of driving. There were tons of open fields filled with either grass or wild flowers. As the elevation increased, it got windier. When the wind blew the flowers in the open fields, it looked like there were waves. We've studied two kinds of waves so far, transverse and longitudinal. These paricular waves that I saw in the fields were longitudinal, meaning that the waves traveled across from left to right and so did the flowers. Transverse waves are the opposite in a sense that while the wave travels across from left to right, the object creating the wave moves up and down. An example of a transverse wave would be a flag.

The Doppler Effect

A few weeks ago, I visited the Las Vegas Motor Speedway, a NASCAR racetrack. I got to watch cars speed around the track and I also rode in one. As the cars went around the track, the motors made a loud vroom noise and I noticed that the cars demonstrated the Doppler Effect. While watching from the pit, I could hear a change in pitch and volume while the car approached me and then sped passed me. They sounded like the motors made different noises as they drove by. However, when I was actually in the car, I realized that the motor made a constant vroom and sounded the same the entire time.

As the cars drive by, you can hear the sound of the motor change.

From inside the car, the engine makes a constant roar.