Physics on trip

PHYSICS DURING MY TRIP
Only on my trip for one and a half days, I noticed a lot of physics! Just at the airport I noticed the physics of the airplane and the metal detector. As I was going through TSA I saw the metal detector and immediately remembered the facts I learned about magnetism. One of the equations I learned from my magnetism chapter was that F=qvBsintheta. The factors that influence the amount of magnetic force of a positive charge in a magnetic field (right hand rule number one) is velocity. The speed of an electron is directly proportional to the force. The faster the electron moves, the stronger the force. In relation to the metal detector, when you are wearing something magnetic while walking under the machine, the faster you walk through it, the easier it is to detect your metal object. It is better to walk slowly through the magnetic detector, if you don't wish to be caught.

At the at airport I was sitting near the window and thought about the physics of an airplane. What is so cool about understanding how an airplane is able to fly is that you have to know all of Newton's three laws. To review, the first law is every object remains at rest unless acted upon by an external force. In order for the airplane to fly you need horizontal and vertical motion. So for the airplane to move horizontally, there must be more "thrust" than "drag". For the airplane to move vertically, the lift must be more than the mg (weight) of the plane. The second law is F=ma. This equation defines the amount of force produced by lift needed to overcome the effects of gravity. Newton's third law states that for every action there is an equal and opposite reaction. This is why airplanes need wings. Depending on the angle of the wing, the airplane can have more lift from the air. So the wing pushes downward on the air, while the air pushes equally as hard upward. Even though there are other principles and science explanations of how an airplane flies, based on the physics that I have learned so far, this is how I perceive the physics of a plane.

MAGNETIC FIELDS

 

       One of the topics I learned in chapter 30, magnetic fields, is ferromagnetism. Ferromagnetism is a strong magnetic effect exhibited by the atoms of certain elements, notably iron. It is the cause of the magnetic field of commonly used magnets. It is the basis of the most familiar type of magnetic devices. For example seeing a magnet affixed to a refrigerator door. The three common elements that exhibit ferromagnetism are iron, nickel, and cobalt. Ferromagnetism is caused by the property of electrons known as spin, the angular momentum of an electron. Even though all matter has electrons, most materials fail to exhibit ferromagnetism because in most materials, the spin of each electron cancels out the spin of another electron in the same atom with which it is "paired." As a result, there is no magnetic field.

       The exterior of a refrigerator is typically not magnetic, yet if it is made of ferromagnetic metal, magnets will stick to it. Magnets will stick to the refrigerator because the magnet induces a temporary magnet in the refrigerator's surface. The actual magnet, and refrigerator's exterior then are attracted to each other. The picture of the lady on the calender sticks to the side of my brand new refrigerator. That is an example of ferromagnetism. However, the shiny silver part of my new refrigerator fails to attract magnets. That part of the refrigerator is not made up of either iron, nickel, or cobalt. My old white refrigerator was able to attract all the magnets in the other picture below.

 



  

Side of the refrigerator! Magnetic calnder

Magnets galore! I bought the Vegas one



My brand new shiny silver refrigerator

 

 

Static Electricity

Coming Home



Me (yeah I have to wear glasses) and keeper Jamie Rosenberg, finally coming home!!

 On December 31, 2011 the 'Iolani girls varsity soccer team and I would return home from our Arizona tournament. The successful win at the tournament felt satisfying. Unfortunately we had to leave on Christmas day. Luckily, we would return home for the first day of the new year. I had not taken physics yet, so I was not able to explain why my hair would stand up (I do not have much common sense either). I have a lot of baby hair so having all my hairs stand up was annoying. From physics I learned the three ways to create charged objects: friction, contact, and induction. Specifically pertaining to the physics of why my hair stood up, my hair became a charged object through friction. Sitting on the plane the back of my head would rub against the head seat. By friction my hair would gain electrons while the seat would lose electrons. Electrically charged, the strands of my hair would repel each other because each of them carries a negative charge. There are many instances like in a long car drive where your head rubs against the seat head. Being on the plane makes the static electricity even more obvious, however. When it is dry, like on the plane, there is less moisture in the air. Water is polar where one end is slightly positive and other end slightly negative. The polar quality of water prevents static electricity as charged objects become neutral. The dry air in the plane has less moisture so there is more static electricity. The cold air, from being so high up in the sky also adds to the severity of static electricity.