The Inside Scoop of the Toaster Oven

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The Inside Scoop of the Toaster Oven

• Alexa Fox and George Bonnewell

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History

• Earliest toaster
• Manual toaster with no moving parts
• Bread was just placed on the rack and by turning
  the rack, the bread got toasted. (pictured on
  left)
• Semi-Automatic toaster
• Includes a bell that lets you know when the toast
  is ready
• Thermostatic switch to control the temperature
• Todays toasters
• Automatic toasters
• Electric current heats the bread
• Timing device to control toast process

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How a Toaster works

• Toasters use the simple idea of resistance to
  provide heat, do work, and prepare the desired
  finished product. From the time the toaster is
  plugged in, to its final spring loaded pop, a
  toasters mechanisms can be clearly explained by
  any Physics 001 student.
• In order to provide heat, toasters usually use a
  material like Nichrome (comprised of nickel and
  chromium) and weave it in bands throughout the
  inside of the toaster. (pictures on left) This
  material is of high resistance, and is generally
  an alloy.
• On an atomic scale, when electricity passes
  through an object with high resistance the
  particles collide more often, resulting in the
  loss of kinetic energy, or transfer of kinetic
  energy to heat. Because the collisions make the
  atoms passing through the material vibrate, they
  become hotter than the surrounding medium (air in
  this case) and the heat is transferred to the
  food placed inside the toaster.
• The change in kinetic energy equals the work
  done, which equals 1/2mv2 1/2mv2 (final
  initial).
• This example stays true to the Law of
  Conservation of Energy, because energy is neither
  being destroyed or created, but is kinetic energy
  being transferred into heat which we learned
  about in class this semester.

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How a toaster works continued

• Although you can use many different alloys to
  create thermal energy and heat your toast, one
  still encounters the problem of getting the toast
  out of the toaster. This is where resistors and
  capacitors come into play, which were discussed
  in class this semester.
• From the moment the toast is pressed down into
  the toaster, a small electro-magnet holds the
  handle of the toaster down. (This is where the
  spring loaded jump comes from at the end) After
  that, a small circuit board in the toaster starts
  charging a capacitor. In simple terms, a
  capacitor stores a charge in a circuit. This
  capacitor is paired with a resistor, just like
  the ones demonstrated online while in class.
  Once the voltage in the capacitor reaches a
  designated level, the electro-magnet is turned
  off and the toast pops up.
• To determine the darkness of ones toast, the dial
  on the outside of the toaster changes the
  resistance on the resistor that is paired with
  the capacitor. Changing the resistance in the
  capacitor will affect how long it takes the
  capacitor to charge, and how long it takes to get
  to the designated voltage release level for the
  toast. Because Voltage Current x Resistance,
  less resistance or more resistance will determine
  how long it takes for the voltage to build up.
  (in the toasters case) Voltage is also another
  topic that was discussed in class.

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New Insight

• We now know how our bread and bagel are toasted
  every morning. Something that seems so easy is
  actually so complex and takes a lot of work. Our
  job is just to put the bread in the toaster and
  the toaster, this little machine, does the rest
  of the work. Our bread would be cold every
  morning without this fabulous invention. Within
  the toaster, electricity is flowing through the
  metal coils and kinetic energy turns into thermal
  energy. The thermal energy is what allows your
  toast to turn brown and warm. Heat is not just
  created from a fire. Heat can also be created
  from electricity, like in a toaster.
• From start to finish a toaster combines the
  principles of electricity and magnetism, as well
  as the principles of work, and the transfer of
  energy to get the job done. The toaster executes
  basic physics principles, yet if one used copper,
  a low resistance material generally used for
  wiring, this process would not have worked.
  Understanding these basic principles plays a
  large role in the ability for a toaster to
  provide its simple service.

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Works Cited

• (2012). Physics and how machines work. Burn an
  Energy Journal , Retrieved from
  http//burnanenergyjournal.com/energy-science/phys
  ics/
• Brain, M. (n.d.). How toasters and capacitors
  work. Retrieved from http//home.howstuffworks.com
  /toaster2.htm
• (1998 ). Toasters The inside story. Hotwire,
  Retrieved from http//www.toaster.org/works.html