Reflection

A couple years ago, taking pictures of our reflections in mirrors was one of the funnest things to do. This is my friend and I at karate practice. I never realized that our reflections have something to do with physics. The image is created from light hitting off the mirror and back to my eye. The angle of incidence is equal to the angle of reflection when an object is reflected to form an image of that same object. Although my image looks like it is being created inside of the mirror, it is actually the same distance I am from the mirror, but behind the mirror. Physics always pops out of no where.

Transformers Extra Credit

Waimalu Park, Sear's Distribution Center, H3, Newtown Estates, Times Coffee Shop in Kailua, Entrance to H3

Electromagnets

This spring break, I went on the California College Tour, and we went to Disneyland on one of our free days. When we went to ride the Twilight Zone in California Adventure, I remembered what we learned in class about electromagnets controlling the falling elevator. An electromagnet has the same characteristics of a permanent magnet, except an electromagnet works when electricity is present, instead of all the time. A magnet is attracted to the elevator, and since it is controlled by electricity, it can be turned on and off. This lets the elevator drop at a high speed for one moment and come to a stop at another moment.

Sound

While in my car, I remembered what we had learned in class so far about sound waves. In this video, the song is being played at a lower volume, then I turned the volume higher. Looking at the singer's voices, the two have different frequencies and amplitudes. Jason Mraz has a lower frequency (lower pitched), while Colbie Caillat has a higher frequency (higher pitched). They also sing some parts of the song louder than others, which would make the amplitude of a sound wave bigger. Although the singing changes frequency every time the singer changes notes, the beat of the song remains the same. Therefore, if I were to analyze one of the beats, the frequency would remain the same at any volume, but as I turn the volume higher, the amplitude of the sound wave would increase. Physics is everywhere.

Motor and Electric Meter Extra Credit

Magnets

This is a picture of the side of my refrigerator. My mom put a lot of these heart magnets on it, but I never realized they were related to physics. An object is a magnet when it creates a magnetic field and exerts a magnetic force. A bigger magnetic field creates a stronger magnet. The magnets have a north and south pole on them, and they are attracted to the metal of the refrigerator. They are strongest at their poles, instead of the center.

Circuits

While I hung out with Robbie this weekend, he drove his mom's car. However, he couldn't drive the car at night time because one of the headlights burnt out, so he had to switch cars to drive me home. Anyways, I found this is related to exactly what we are learning about in Physics class. A circuit must be complete in order for things such as light bulbs to function properly. As shown in this picture, the light bulb in the headlight does not work because the filament, that once connected the circuit in one path of traveling electrons, burnt out, so the circuit is no longer complete. Even though the car battery is still working to light the other lights on the car, that one headlight does not work because of the unclosed circuit.

Voltage & Extra Credit

This weekend for the BJ Penn fight, we had a bbq. Everyone brought all different types of foods. Anyway, while I was watching my dad grill all the meat, I noticed he had to just push this small button to fire up the whole grill. This made me wonder how one small button can start up the gas grill. Then, I realized the button was a electronic ignition and that it had a small voltage duracell battery powering the button. We just learned that voltage equals potential energy over charge and that it is a ratio. Since charge is measure in coulombs, there are a lot of electrons involved in lighting a grill. Even though a small dry cell battery was used, it was able to light the grill. I read that a bbq lighter uses something called piezoelectricity to generate a nice spark that lights the grill. Piezos are some kind of crystals. When you apply pressure to them, you get a charge separation within the crystal and a voltage across the crystal that is sometimes extremely high.




For this experiment, I tried it many times. It wouldn't work on myself, my mom, my sister, or Blake, so I finally tried it on one of my dogs, Chloe. With Chloe, I could see how the charge balloon made the water bend a little bit. The bending of the water can't be seen very well in the video, but if you listen, you can hear the difference as I bring the balloon closer and farther to the faucet water. Since the balloon received electrons from Chloe by friction, it changed from being neutral to being negatively charged. Water is made up of polar H2O molecules, so when it came closer to the balloon, the positive charges in the water separated from the negative charges and attracted towards the balloon, causing it to bend towards the balloon. My sister and I are going to try this again with a different type of balloon and hopefully it will be more evident.

Center of Mass/Moment of Inertia

This is a picture of my clothes rack where I hang some of my clothes because my closet is too full. As you can see it it standing perfectly fine, but this was not the case before i re-arranged the clothes I put on it. At first, I put all of my heavy jackets on one side and my light dresses and tops on the other side, and one night the whole rack fell over while I was sleeping. I did not expect this to happen but then realized it was because the center of mass was outside of the support area, which is in the middle of the rack. The mass should have been centered towards the middle of the rack instead of having heavy clothes on one side and lighter clothes on the other. It also could be seen as the heavier side creating a torque, and since there was more moment of inertia on that side (due to its bigger mass), that made it easier to fall over. After whole clothes rack toppled over, I realized I should evenly put my lighter clothes on it.