physics 2

• whAT refers to a phenomenon of inducing voltage by changing the magnetic field around a conductor

  Electromagnetic Induction
• what do you call an energy transfer to electric circuit per unit of electric charge?

  Electromotive force
• what happen to the magnetic field if the magnet is accelerating towards the coil

  Increasing
• Weber/wb


  SI unit of magnetic flux
• what law refers to an electric field is created by time-varying magnetic field

  Faraday's law
• A bar magnet moving towards the loop will generate a current in a conducting loop
• what are the lines formed in the magnetic field

  close
• how can we induce an electromotive force in circuit

  1. Changing magnetic flux density
  2. changing the angle
  3. CHangine the are of the circuit
• What law states the "the direction of an induced current is such that its own magnetic flux opposes the original change in magnetic flux that induced the current"?

  Lenz's law
• term that refers to an amount of force the electrons are moved in a circuit

  voltage
• what happens to the magnetic field when placed in a circular loop

  increasing
• when a bar magnet is dropped from above and falls through the loop of wire the current in the loop always flows in a clockwise direction
• what is the reason why power companies supple alternating current and not direct current

  it is easier to transmit alternating current
• particle and a wave


  its essential theory was further evolved from electromagnetics into quantum mechanics.
• Albert Einstein believed that light is a particle (photon) and the flow of photon is a wave
• Isaac Newton believed that light is a particle led to the discovery that white light consist of mixture of colors.
• Christiaan Huygens the first detailed wave theory of light. Which he was able to derive the law of reflection and fraction.
• We use the symbol c, which comes from word celerity, meaning "speed or swiftness," to represent the speed of light.
• the approximate speed of light in a vacuum is 3.00 x 108 m/s.
• Electromagnetic waves are transverse waves with a wide range of properties and uses

  • transfer energy from the source of the waves to an absorber.
  • can travel through a vacuum such as in space.
  • all travel at the same velocity through a vacuum
• Light waves are just one example of a large group of waves known as electromagnetic waves
• The electromagnetic waves that our eyes can detect are known as visible light
• Electromagnetic waves are produced in nature when an electron in an atom oscillates back and forth.
• Electromagnetic waves form a continuous spectrum of waves.

  •  waves with a very short wavelength, high frequency and high energy

   waves with a very long wavelength, low frequency and low energy.
• Radio Waves The lowest-frequency electromagnetic waves of practical importance are radio waves, in the frequency range 106 Hz to 109 Hz.
• Global Positioning Systems (GPS) measure the time it takes a radio wave to travel from several satellites to the receiver, determining the distance to each satellite.
• • A radio picks up radio waves through an antenna and converts it to sound waves.
• Microwaves 


  Electromagnetic radiation with frequencies from 109 Hz to about 1012 Hz are referred to as microwaves.
• RADAR (Radio Detection and Ranging)

  •Used to find the speed of an object by sending out radio waves and measuring the time it takes them to return.
• infrared Waves

  Electromagnetic waves with frequencies just below that of red light—roughly 1012 Hz to 4.3 x 1014 Hz—are known as infrared (IR) waves. These waves can be felt as heat on our skin but cannot be seen with our eyes. Many animals have infrared receptors that allow them to "see" infrared radiation.
• Thermograma

  picture that shows regions of different temperatures in the body.  Temperatures are calculated by the amount of infrared radiation given off. 
• Visible Light

  The spectrum of visible light is represented by the full range of colors seen in the rainbow.
• Ultraviolet Light

  When electromagnetic waves have frequencies just above that of violet light—from about 7.5 x 1014 Hz to 1017 Hz—they are called ultraviolet (UV) rays.
• X-rays are radiation in the range of the electromagnetic spectrum between 1017 Hz and 1020 Hz.
• electromagnetic waves with frequencies above 1020 Hz are referred to as gamma rays.
• Electromagnetic Induction was first discovered way back in the 1830’s by Michael Faraday.
• Faraday noticed that when he moved a permanent magnet in and out of a coil or a single loop of wire it induced an ElectroMotive Force or emf, in other words a Voltage, and therefore a current was produced.
• Electromagnetic Induction is the process of using magnetic fields to produce voltage, and in a complete circuit, a current.
• Michael Faraday first discovered it, using some of the works of Hans Christian Oersted. His work started at first using different combinations of wires and magnetic strengths and currents, but it wasn't until he tried moving the wires that he got any success.
• The first step to understanding the complex nature of electromagnetic induction is to understand the idea of magnetic flux.