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58 Cards in this Set
- Front
- Back
Define light |
Is the form of energy you can see |
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List natural light sources |
-Sun -Stars -Flames & sparks |
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List Artificial light sources |
-Matches -Flashlight -Lightbulbs |
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Define radiates |
Light spreads out |
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Define radiation |
Energy transfer does not require matter |
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Define radiant energy |
a light that travels by radiation |
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light can be transformed into ____ and list examples |
-thermal energy ex. Absorbation by a sweater in sunlight -electrical energy ex. Solar cells change light into electricity -chemical energy ex.trees absorb sunlight to make chemical energy |
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Define Incandescence |
Emisson of visble light from heated object |
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Energy tranformation of incandescent light source |
Electrical energy ---> Thermal energy -----> Visible light energy |
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Define fluorescence |
Absorbs ultraviolet light and emits some of the energy |
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Energy transformation of fluorescence |
Ultraviolet light energy ----->Energy aborbed by particles ---> Visible light energy |
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Energy Pathway for a fluorescent source |
Electrical energy ---> Energy absorbed by mercury particles ----> ultraviolet light energy -----> energy absorbed by phosphor particles ---> Visible light energy |
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Fluorescent tubes & incandescent light blubs disadvantages & advantages |
Disadvantages -more expensive to make -more diffult than Incan to dispose -phosphor & mercury vapour is toxic Advantages -wastes less energy -more energy efficent |
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Define Phosphorescence |
Absorbs light & then slowly realises light over time |
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Define Chemiluminescence |
Chemical reaction produces energetic particles that give off visible light energy |
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Define Bioluminescence |
Chemical reaction in the body of a living creature |
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Define luminous |
All objects that emit light |
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Define non-luminous |
All objects that do not emit light |
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How to find out cost of lighting |
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What is the ray model of light? |
Based on light that travels in straight lines in all directions when a light strikes a surface its path can be determined. |
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List the following surfaces that light light strikes |
-transparent lets all light through -translucent lets some -opaque lets none |
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Define Reflection |
Is the process in which light strikes a surface and bounces back off that surface |
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Label |
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Define a plane mirror |
A reflective surface that gives uniform results |
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Law of reflection |
The angle of relection equals the angle of incidence |
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Define convex mirrors & examples |
Bludges out , image appears farther & smaller away. Ex. Security mirrors , passenger side of cars |
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Define concave mirrors & examples |
Curved inside, makes image appear much closer & larger. Ex. Makeup mirrors |
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Define virtual image |
When you see the image when you look into a mirror. |
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Define refraction |
Bending of light when it travels from one mediuim to another |
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Define double concave lenses |
Is thinner & flatter in the middle that around the edges |
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Define double convex lens |
Thicker in the middle than around the edges |
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Define near-sightness |
When image falls short of the retina (eye has a longer shape than a regular eye) trouble seeing images far away |
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Define far-sightness |
When image falls behind retina (eye shorter than normal eye) trouble seeing images close up |
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How to fix near-sightness? |
With concave lense allows image to fall on retina |
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How to fix far-sightness? |
With convex lenses allows image to fall on retina |
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Define Retina |
Light-sensitive area where the image is formed |
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Label each part of the camera |
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List the corresponding parts of the camera & eye & definitions |
Film=retina Define: created visual image signals
Diaphragm=iris Define:controls diameter & size , of pupil, controls amount of light
Lens=Lens Define:changes focal distance
Foccusing ring=cilliary muscle Define:changes lens shape for foccusing
Optic nerve Define: transfers visual information
Shutter Define: Allows light to pass for a certain period of time |
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Label |
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Define accomadation |
The process of changing the shape of the lens to adjust for different object distances |
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Define near point |
The shortest distance at which an object is in focus |
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Define far point |
The longest distance in focus |
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Define diaphragm |
Is a device that controls the aperture |
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Define aperture |
The opening of a lens or optical system |
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Define shutter |
Device that limits the passage of light |
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Define iris reflex |
The natural adjustment in the size of the pupils |
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Define optic nerve |
When the cells in the retina detect light, they produce small electrical impulses that travel from the retina to the brain |
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Define blind spot |
The point where the optic nerve enters the retina does not have any light-sensing cells. |
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Define a refracting telescope |
light from a distant object is collected and focussed by a convex lens called the objective lens. A second lens, called the eyepiece lens, works as a magnifying glass to enlarge the image |
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Define objective lens |
Focused by convex lens |
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Define eyepiece lens |
Works as a magnifying glass |
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Define a reflecting telescope |
uses a concave mirror to collect rays of light from a distant object. The mirror is called the primary or objective mirror. It forms a real image, which is then magnified by the eyepiece lens |
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Define objective mirror |
Concave mirror to collect rays from distant object |
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Label the refracting telescope |
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Label the reflecting microscope |
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Define binoculars |
two reflecting telescopes mounted side by side. |
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Define prisms |
In binoculars, the telescopes are shortened by placing glass blocks inside , glass blocks. Serve as plane mirrors |
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How did Telescopes make an impact |
an explosion of scientific knowledge about the universe. No longer were plan- ets just wandering points of light in the dark sky. They became worlds of their own. For astronomers, the starry sky became an expanding cosmos of galaxies linked in truly gigantic formations. |