Light Shadow And Reflection
Chapter-11
Light
Energy
• Energy, in physics, the capacity for
doing work
• Because of energy, an object can
perform work or can heat the other
object or things.
Energy
Light
Light
c
Sources of light
Natural Artificial
Natural Sources of Light
Sun Stars
Natural Sources of Light
Fireflies Glowworms
Natural Sources of Light
Jellyfish Angler fish
Natural Sources of Light
Bush Fires Lightning
Artificial Sources of light
Light Bulb Torches
Artificial Sources of light
Lamp Lighter
Artificial Sources of light
Flame by matches Candle light
c
Objects
Luminous
Objects
Non luminous
objects
Luminous Objects
Non luminous objects
Luminous and Non-Luminous Objects
Luminous objects
• Objects that can emit light
energy by themselves are
known as luminous
objects.
• The luminous objects are
visible as they emit light
on their own.
• E.g. Sun, Burning Candle
Non-luminous objects
• Objects that cannot emit
light energy by themselves
are known as non-luminous
objects.
• The non-luminous objects
are visible because of
luminous objects.
• E.g. Earth, Moon
Quick Revision
• What is light?
• What is energy?
• Sources of light- Natural and Artificial
• Luminous and non luminous objects

class-6th science chapter-11 (lLight shadow and reflection)

Editor's Notes

  • #2 Hello Students, in this chapter we study about Light Shadow And Reflection
  • #3 Imagine you are in dark room where you are not able to see anything.
  • #4 Your eyes need light to see the things around you
  • #5 So what is light? Light is form of energy
  • #6 So, first understand what is energy? in physics, energy is the capacity for doing work Because of energy, an object can perform work or can heat the other object or things.
  • #7 There are many form of energy, for example wind energy, solar energy, nuclear energy etc.
  • #8 Similarly, light is one of the form of energy.
  • #9 As I said, We cannot see an object in the darkness. It means We need a source of light to make the object visible.
  • #10 There are countless sources of light but they can all be categorized as Natural sources Artificial sources
  • #11 Some of the natural sources of light as follow The Sun is the major natural source of light for the earth. Energy comes out as heat and light. Do you know? the light from the sun is one of the major factors behind the sustainability of life on earth Star produces light too, but only a small or no amount of it reaches the earth because of the huge distance.
  • #12 Fireflies Glowworms generally found in New Zealand caves
  • #13 Jellyfish Anglerfish
  • #14 Bush fires and lightning are the natural source of light
  • #15 Now examples of Artificial Sources of light are Light bulb torches
  • #16 Lamp Lighter
  • #17 Flame by matches Candle light Etc are artificial source of light
  • #18 There are countless sources of light but they can all be categorized as Natural sources Artificial sources
  • #19 Luminous Objects-Objects that can emit light energy by themselves are known as luminous objects. Forexample Sun Bulb Candle Stars etc
  • #20 And Non luminous objects-Objects that cannot emit light energy by themselves are known as non-luminous objects. For example Earth painting Moon Chair etc
  • #21 So what is the difference between luminous and non luminous objects Luminous Objects that can emit light energy by themselves Where as non luminous Objects that cannot emit light energy by themselves The luminous objects are visible as they emit light on their own. And The non-luminous objects are visible because of luminous objects. Sun, Burning Candle are example of luminous objects Where as earth and moon are example of non luminous objects
  • #22 So till now we have understood about What is light? What is energy? Sources of light- Natural and Artificial source of light And the last one was difference between Luminous and non luminous objects