Difference between revisions of "4Energy-5"

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(New page: ==Outcomes== * Pupils understand that thermal energy is transferred in three ways: conduction, convection and radiation. * Pupils understand the process of evaporation as a decrease in the...)
 
(Popcorn example)
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==Starter==  
 
==Starter==  
====Popcorn example====
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* Popcorn can be cooked in three ways:
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** By conduction in a pan with oil.
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** By convection in a [http://images.google.co.uk/images?q=hot%20air%20popper hot-air popper].
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** By radiation in a microwave.
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==Main Body of Lesson==
 
==Main Body of Lesson==
 
* Emphasise to pupils that "cold" doesn't move - thermal energy always moves from higher concentration (hot objects) to lower concentration (cold objects). You can draw parallels with biological examples that they may be familiar with (e.g. osmosis).
 
* Emphasise to pupils that "cold" doesn't move - thermal energy always moves from higher concentration (hot objects) to lower concentration (cold objects). You can draw parallels with biological examples that they may be familiar with (e.g. osmosis).

Revision as of 10:00, 19 February 2012

Outcomes

  • Pupils understand that thermal energy is transferred in three ways: conduction, convection and radiation.
  • Pupils understand the process of evaporation as a decrease in thermal energy.

Specification References

4.6 recall that energy transfer may take place by conduction, convection and radiation

Starter

Main Body of Lesson

  • Emphasise to pupils that "cold" doesn't move - thermal energy always moves from higher concentration (hot objects) to lower concentration (cold objects). You can draw parallels with biological examples that they may be familiar with (e.g. osmosis).
  • Explain the processes of conduction, convection and radiation using heat transfers circus.
  • Show pupils demonstrations of conduction, convection and radiation.
  • Explain the process of evaporation as a decrease in average kinetic energy.
  • Show pupils evaporation demonstration.

Practicals/Demonstrations

Conduction demonstrations

  • Wood/aluminium plates (identical in appearance) with ice cubes - one melts very quickly, one very slowly.
  • Rods of different metals (e.g. copper, aluminium) with embedded thermochromic thermometers (or alternatively, covered in wax) can show the progress of conduction.

Convection demonstrations

  • Convection tubes; one with potassium permanganate and spirit burner; one with water and glitter.
  • Smaller convection tube with can be "operated" by heat from a pupil's hand.

Radiation demonstrations

Evaporation demonstration

  • Dab a small amount of alcohol from a cotton bud onto the back of pupils' hands.


Plenary

Homework

Additional Information

Resources Required

  • Microwave oven
  • Microwaveable popcorn
  • Popping kernels

Skills Addressed

  • Spear fishing

Safety/Hazards

  • Flying popcorn could injure.
  • Hot popcorn is hot.
  • Pupil may choke on popcorn.

Energy Outline

Energy (3rd Form)