Physics Project

Electromagnetism and Magnetism

Richard Feynman

Richard Feynman developed an approach to Quantum Mechanics governed by a principle of least action. He also corrected inaccuracies in early formulations of Quantum Electrodynamics. Richard Feynman also did many other remarkable things:

· He was recruited to work on the U.S. Atomic Bomb project. He was the youngest group leader in the theoretical division. With some help, “he devised the formula for predicting the energy yield of a nuclear explosive.” He helped create the atomic bomb.

· Resolved some mystery results the old Quantum Electrodynamics theory produced.

· Created simple diagrams that “that are easily visualized graphic analogues of the complicated mathematical expressions needed to describe the behavior of systems of interacting particles. This work greatly simplified some of the calculations used to observe and predict such interactions.”

· Provided a quantum-mechanical explanation for the theory of super fluidity

· With a fellow physicist, he devised a theory that accounted for most of the phenomena associated with the weak force, which is the force at work in radioactive decay.



Electromagnetic Induction

"Electromagnetic induction occurs when a circuit with an alternating current flowing through it generates current in another circuit simply by being placed nearby. An alternating current is the kind of electricity flowing through power lines and home wiring, as opposed to a direct current, which we get from batteries. How does one circuit cause a current in another without touching it, and what does any of this have to do with magnetism? Before we get into that, we need to look at a few principles linking magnetism and electricity:
  1. Every electric current has a magnetic field surrounding it.
  2. Alternating currents have fluctuating magnetic fields.
  3. Fluctuating magnetic fields cause currents to flow in conductors placed within them, which is also known as Faraday's Law.
Adding these three properties together means that a changing electric current is surrounded by an associated changing magnetic field, which in turn generates a changing electrical current in a conductor placed within it, which has its own magnetic field…and so on"
"A electric motor is a device for transforming electrical energy into mechanical energy; an electric generator does the reverse, using mechanical energy to generate electricity. At the heart of both motors and generators is a wire coil in a magnetic field. In fact, the same device can be used as a motor or a generator.

When the device is used as a motor, a current is passed through the coil. The interaction of the magnetic field with the current causes the coil to spin. To use the device as a generator, the coil can be spun, inducing a current in the coil."

So why does this all matter? How does Electromagnetic Induction even affect our lives?

Electromagnetic Induction has brought electricity into our lives. Electricity has "grown to become the basis of our comfort, providing our heat, lighting and climate control, and powering all of our appliances, be they for, cleaning, or entertainment." Electromagnetic Induction has allowed luxuries into our lives, like cooking!
Electromagnetic Induction allows a generator to power an electric toothbrush so we can brush our teeth at a touch of a button to get our teeth clean and sparkling.

Electronics

Thankfully, humans invented wireless communication devices! Cell phones are actually extremely sophisticated radios. They transmit a number of frequencies. Induction incurs a lot of energy transferred into heat. Induction was one of the first methods of detecting touch on a surface. They connect to towers, and We can talk, text, and surf the web at the tip of our fingers.

Computers

A computer has a motherboard, which is a large circuit board. Computers must use electromagnets for power. "The electromagnet is a device that transforms an electrical current into a magnetic field, As long as an electrical current flows through the electromagnet it has a magnetic field. If the current is disrupted the object is no longer a magnet. The process that causes this, electromagnetic induction, is a result of the unique relationship between electricity and magnetism e can surf the web, create presentations, and access the world on computers.

Washers and Dryers

Washers and dryers allow us to wash and cry our clothes with ease. They are easy to use and quickly get the job done. Washing Machines, and Drying Machines use a sort of motor in order to move the clothes back and forth. The motor used can be made with an electrical force (or pulses) creating strong electromagnetic fields. Electric motors allow electricity to flow, creating the magnetic fields needed.

Television

Electromagnetic Induction allows us to be entertained by television, and gaming devices such as an Xbox, or Wii. A few TVs in use today rely on a device known as the cathode ray tube, or CRT, to display their images. LCDs and plasma displays are other common technologies. It is even possible to make a television screen out of thousands of ordinary 60-wattlight bulbs! An anode, is a terminal in which current can enter into electrolytic cell. The anode is positive, so it attracts the electrons pouring off the cathode. In a TV's cathode ray tube, the stream of electrons is focused by a focusing anode into a tight beam and then accelerated by an accelerating anode. This tight, high-speed beam of electrons flies through the vacuum in the tube and hits the flat screen at the other end of the tube. This screen is coated with phosphor, which glows when struck by the beam. Without electromagnetic induction creating electricity, a television would not work.


Cited Sources:

"Richard P. Feynman." Britannica School. Encyclopædia Britannica, Inc., 2013. Web. 20 Mar. 2013. <http://school-preview.eb.com/levels/high/article/34161>

Brain, Marshall. "How Television Works" 26 November 2006. HowStuffWorks.com. <http://electronics.howstuffworks.com/tv.htm> 02 April 2013.

"Applications of Electromagnetic Induction." Applications of Electromagnetic Induction. Boston University, 22 July 1999. Web. 07 Apr. 2013. <http://physics.bu.edu/~duffy/PY106/Electricgenerators.html>.

Brain, Marshall, Jeff Tyson and Julia Layton. "How Cell Phones Work" 14 November 2000. HowStuffWorks.com. <http://electronics.howstuffworks.com/cell-phone.htm> 08 April 2013.

"What Are the Application of Electromagnetic Induction?" WikiAnswers. Answers, n.d. Web. 08 Apr. 2013. <http://wiki.answers.com/Q/What_are_the_application_of_electromagnetic_induction>.