unit 3 Light and Optics Flashcards
what are some examples of natural light
The Sun, Moon, Star, Fire, Fireflies, jellyfish, Lightning
what are examples of artificial light
Lantern, Candle, Oil lamps, Street lights, Computer, TV, Lightbulb
what is light
light is a form of visible energy
how can you break up light
light can be broken up by using a prism the prism break up the light which shows the all the colours of the rainbow
what is the definition of reflection
is the process in which light strikes a surface and bounces back off that surface. Light reflecting from a mirror allows you to see an image of yourself.
what is the law of reflection
principle that when a ray of light, radar pulse, or the like, is reflected from a smooth surface
How is an image formed in a mirror?
Light from some luminous source on an object. The light reflects off all points on the object in all direction
How do convex and concave mirrors work?
A concave mirror is curved like the inside of a shiny bowl.
A convex mirror bulges outward like the surface of a shiny, helium-filled party balloon.
What are the two different types of reflective surfaces? (p. 197)
There is a smooth and flat reflecting surface and a rough reflecting surface. In a smooth surface the reflection line is straight and on a rough surface, the reflection line is not straight because of the surface.
How is the Law of Reflection applied in everyday life? (p.198-199)
The law of reflection can be used in a everyday life for safety such as the reflector that is built, a bike flash when the light from the vehicle hits the reflector and it makes it flash
What is fibre optics?
use of thin flexible fibres of glass or other transparent solids to transmit light signals
Give an operational definition for refraction (p.200)
A change of direction that light undergoes when it enters a medium with a different density from the one through which it has been traveling
Incandescent
An object is heated to such a high temperature that it emits visible light. A good example of an incandescent light source is an old style light bulb. Try and touch one of those bulbs, you will burn your finger…badly!
Fluorescent
An electrode heats mercury vapours and they, in turn, give off ultraviolet light (radiation). A phosphor coating absorbs this radiation and causes the bulb to glow. A good example will be
Phosphorescence:
Light NRG is absorbed by particles that store this NRG for a while and is later released as visible NRG. A good example of a phosphorescent light source would be glow in the dark stickers.
