L1 Seeing Things
1) Does the “Eye-Brain” see the indicated ray of light? Yes / No (1 mark) Explain how the ray could be seen. (2 marks) ______
2) “Light is a type of energy our eyes are sensitive to.” is called an ______ definition. (1 mark) Explain why (2 marks) ______
3) Light travels in Straight lines. This is called ______. (1 mark)
4) Which Eye/ Brains can see the Object?
5) The “colours” of light are called a ______(1 mark)
6) White Light is made up of shades in order ______, ______, ______, ______, ______, and ______. (6 marks)
7) A mnemonic is just ______ (2 marks)
8) Most light sources are made up of ______ (1 mark)
9) The Conceptual definition of light is; ______ (2 marks)
10) The Visible Light Spectrum is a very small part of a much larger spectrum called the ______ (1 mark)
11) The Electromagnetic Spectrum is made up of the following types of radiation in order ______, ______, ______, ______, ______, ______, ______, (7 marks)
12) ______ objects emit light rays produced from other energy sources. (1 mark)
13) ______ objects scatter the light rays from luminous objects.(1 mark)
14) Light rays travel from the object to the observers eye through a ______. (1 mark)
15) A ______ medium allows nearly all the light rays to pass straight through unaltered. Example ______. (2 marks)
16) An ______ medium absorbs or scatters all the rays. Example______. (2 marks)
17) A ______ medium transmits and scatters the rays. The medium indicates whether it is being illuminated but the object cannot be clearly seen. (1 mark)
18) On a ray diagram how is the objects location indicated? (3 marks) ______
19) On a ray diagram what does the objects apparent size depends (3 marks) ______
20) On the ray diagram to the right show the rays that help Wendy’s Eye-Brain determine size (height) of the candles. (3 marks) Please explain in words.
21) On the ray diagram to the right show the rays that help the Wendy’s Eye-Brain determine location (distance) of the candles. (3 marks) Please explain in words.
22) On the ray diagram to the right show why Captain Wendy’s Eye-Brain might be confused about the candles size (height) or location (distance). (3 marks) Please explain in words.
23) What is the Moon illusion? (3 marks)
24) Visible Light can be produced from many energy sources. Use the internet or other resources to fill in the following table (18 marks)
Type of Light Emission / Energy Source and Explanation / ExamplesAstronomical objects
Bioluminescences
Triboluminescence
Chemoluminescence
Fluorescence
Phosphorescence
Incandescent
Combustion
Light-emitting diodes
Energy Sources and Explanation
A material is heated up (given thermal energy) until light is emitted. This is also called black body radiation)
A term used when energy generated is a result of a chemical reaction with limited emission of heat
Energy from chemical reactions in living organisms
Energy generated when chemical bonds are broken when a material is pulled apart, ripped, scratched, crushed, or rubbed
Most of the light produced is the result of a exothermic chemical reaction . The bright, yellow part of the flame is the produced by carbon polymers heated to incandescent .
Nuclear energy released due to intense heat, pressure and temperature
Visible light is absorbed by the material then remitted as light of a different wavelength (colour).
Visible light is absorbed by the material then remitted over a long time period as light of a different wavelength (colour).
Works like a photovoltaic cell in reverse. It’s a device that converts electricity directly into light with very little heat.
Examples
"glow-in-the-dark" materials which are "charged" by exposure to light.
breaking sugar crystals in Wint-O-Green Life Savers) and peeling adhesive tapes
common fluorescent tube ,compact fluorescent lamp
Conventional incandescent light bulbs
Fireflies, jellyfish, Antarctic krill
Glow Sticks
Indicators and signs where low energy consumption is required, highly efficient, environmentally friendly, lighting with very long lifetime
paraffin candle, kerosene lamps and coal oil lamps
Sun and Stars