3,913
edits
Changes
From Karnataka Open Educational Resources
no edit summary
= Teaching Outlines =
= Teaching Outlines =
==Concept #1 - Light is a form of energy==
==Concept #1 - Light is a form of energy==
===Learning objectives===
===Learning objectives===
#Light is a form of energy and travels as electro-magnetic radiation. There are other radiations apart from light that travel as electro-magnetic radiation.
#Light is a form of energy and travels as electro-magnetic radiation. There are other radiations apart from light that travel as electro-magnetic radiation.
#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.
#The different types of photons are seen by us as different colours.
#There are some kinds of photons that we cannot see – for example heat radiation, X rays, infra-red and ultra-violet rays. We say that light travels as a wave and different coloured lights have different wave-length associated with them.
===Notes for teachers===
===Notes for teachers===
The unit begins by introducing the idea that light is a form of energy. We then look at how this energy is transported from a source to a destination in the form of waves. After a brief description of what waves are and how they actually transport energy the idea that light of different wavelengths are perceived as different colours would be introduced. This would naturally lead to the idea of hues and intensity.
#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>
#The primary source of all energy, including light, is the Sun. All the other kinds of energy that we receive here can be traced back to the sun. 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>
#This radiation can be thought of as waves of different wavelengths. The waves are not of material objects but travelling waves changing electric and magnetic fields. Different wavelengths are associated with different energy levels and different kind of radiation.
#This radiation can be thought of as waves of different wavelengths. The waves are not of material objects but travelling waves changing electric and magnetic fields. Different wavelengths are associated with different energy levels and different kind of radiation.
===Learning objectives===
===Learning objectives===
#The different types of photons are seen by us as different colours.
#The different types of photons are seen by us as different colours.
#There are some kinds of photons that we cannot see – for example heat radiation, X rays, infra-red and ultra-violet rays. We say that light travels as a wave and different coloured lights have different wave-length associated with them.
#There are some kinds of photons that we cannot see – for example heat radiation, X rays, infra-red and ultra-violet rays. We say that light travels as a wave and different coloured lights have different wave-length associated with them.
#White light is a combination of all colours. Different colour lights can be produced from this by absorption and by reflection. The colours of the rainbow spectrum – Violet, Indigo, Blue, Green, Yellow, Orange & Red – ‘VIBGYOR’ or ‘Roy G BIV.’ Black colour is the absence of colour. Objects that are black do not reflect any light but absorb all the energy.
iv. Understand the idea of primary additive colours and primary subtractive colours and how differe
===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.''
''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.''
#How are we able to see? (We see objects because they reflect light).
#How are we able to see? (We see objects because they reflect light).
#What is white light? When do we see white and black? (If they reflect all the incoming white light then we see it as white. If it does not reflect any light but absorbs all of it then we see it as black. If it reflects some colours and absorbs others then we see it as the colour of the light that it reflects. A tomato is red because it absorbs colours other than red and reflects red light. A green leaf is green because it absorbs all light other than green).
#What is white light? When do we see white and black? (If they reflect all the incoming white light then we see it as white. If it does not reflect any light but absorbs all of it then we see it as black. If it reflects some colours and absorbs others then we see it as the colour of the light that it reflects. A tomato is red because it absorbs colours other than red and reflects red light. A green leaf is green because it absorbs all light other than green).
#How are pigments different from light?
* '''Question Corner'''
* '''Question Corner'''
