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Line 42: − '''''These are short notes that the teacher wants to share about the concept, any locally relevant information, specific instructions on what kind of methodology used and common misconceptions/mistakes'''.''<br>+ − + Line 60:
Line 60: − Sun provides us with heat and light. This travels through the near vacuum of space. So there is no material to transport energy. When we block light we also block the heat radiation. Any source of heat also radiates some visible light.
→Concept #1 - Light is a form of energy
#It is possible to look at light and other electro magnetic radiation as a wave or as a particle known as the photon.
#It is possible to look at light and other electro magnetic radiation as a wave or as a particle known as the photon.
===Notes for teachers===
===Notes for teachers===
''These are short notes that the teacher wants to share about the concept, any locally relevant information, specific instructions on what kind of methodology used and common misconceptions/mistakes.''<br>
Light is a form of energy that is transported as electromagnetic radiation but interacts with material particles as discrete packets of energy that are called photons.
Light is a form of energy that is transported as electromagnetic radiation but interacts with material particles as discrete packets of energy that are called photons. Sun provides us with heat and light. This travels through the near vacuum of space. So there is no material to transport energy. When we block light we also block the heat radiation. Any source of heat also radiates some visible light. <br>
===Activity No # 1 - Thought Experiment - Radiation from the Sun===
===Activity No # 1 - Thought Experiment - Radiation from the Sun===
* '''Website interactives/ links/ simulations'''
* '''Website interactives/ links/ simulations'''
* '''Process (How to do the activity)'''
* '''Process (How to do the activity)'''
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Heat a piece of iron and the iron changes colour from a dull grey to red to yellow to white when light of all wavelengths are radiated in addition to the heat. On a cold day the temperature inside a glass house is much higher – why? Because light of a shorter wavelength can travel through glass and is absorbed by the ground and plants. The ground reflects back radiation of a higher wavelength – infra-red and heat radiation. This cannot pass through glass and so the glass house is much warmer.
Heat a piece of iron and the iron changes colour from a dull grey to red to yellow to white when light of all wavelengths are radiated in addition to the heat. On a cold day the temperature inside a glass house is much higher – why? Because light of a shorter wavelength can travel through glass and is absorbed by the ground and plants. The ground reflects back radiation of a higher wavelength – infra-red and heat radiation. This cannot pass through glass and so the glass house is much warmer.