Flaming Food and the Law of Conservation of Energy

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Flaming Food and the Law of Conservation of Energy

• Math and Science
• High School

To Teacher Page To Activity
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Teacher Page

• Content Math and Physical Science
  Conservation of Energy
• Creators Martha Stephenson and Dorothy Walk
• MAP Standards SC
• The learner will be able to understand that
  energy change in a given process can be
  quantified.
• The learner will be able to construct a graph
  from data and analyze the data.

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• Tips for Classroom Use
• Preview the activity before using it with your
  class.
• Journaling
• This activity may be used in conjunction with
  journaling.
• The notebook icon will prompt the student
  
  
  when to journal in
  their notebooks.

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Focus on the process of problem solving with
your studentthey need to understand not only
the facts, but the reasoning behind them. Have
them write their thoughts on paper and then
discuss them as a class.
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Flaming Food and the Law of Conservation of
Energy

• The Law of Conservation of Energy states
• In an insulated system, energy can neither be
  created nor destroyed by ordinary means, but it
  can be changed from one form to another.

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Create a list of different forms of energy.

• Did you include
• Kinetic Energy
• Potential Energy
• Solar Energy
• Chemical Energy

• Radiant Energy
• Mechanical Energy
• Nuclear Energy
• Thermal Energy
• Electromagnetic Energy

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Our bodies take advantage of this law to obtain
energy from foods.

• The energy is measured in Dietary Caloriesthe
  higher the caloric value of a food item, the more
  energy it contains.
• Dietary Calories are actually equal to 1000
  calories and 1 calorie has enough energy to raise
  the temperature of 1 ml of water 1C.

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A Calorimeter can be used to measure the amount
of energy in food. Heres how it works...

• A piece of food is burned below a container of
  water.
• The temperature change of water is recorded
• The amount of heat produced is Q m
  X D T X c

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Calculating Heat

• To calculate amount of heat produced use the
  equation Q m x DT x c
• Q amount of heat produced
• m mass of material
• DT change of temperature
• c specific heat capacity (5.18 J/kg.oC)

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(divert into either math or science)

• Would you like the math or science component of
  this activity?
• Science Math

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Think about it...

• 1. How does taking the temperature of the water
  indicate the amount of energy in the food?
• 2. How can the change in temperature of the
  water be useful to determine the number of
  calories in the food?
• 3. How was the Law of Conservation of Energy
  used in this experiment?

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Using your knowledge of the Law of Conservation
of Energy and procedure for using the calorimeter
you just saware there any possible sources of
error in an experiment like this?
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End of Science Activity
To Math
Bye-bye
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Item of food burned Amount of Heat produced

• Peanuts
• Potato chips
• Hamburger
• Candy bar
• Pepsi
• Popcorn
• 100 g of each food

• 170 J
• 162 J
• 77 J
• 154 J
• 40 J
• 60 J

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Make a Graph

• Graph the food data using the appropriate type of
  graph
• Give your graph a title
• Label the appropriate parts of the graph

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Analyze the Data

• What is the mean?
• What is the median?
• What amount of hamburger would produce the same
  amount of heat as 500 g of Pepsi?

To Science
Adios
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The End