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67 Cards in this Set
- Front
- Back
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Light |
Light is a form of energy that you can see. |
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2 Types of Light Sources |
Natural light source and artificial light source. |
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Radiate |
Light spreading out in all directions. |
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Does light need matter to travel through? |
No, it can even travel in a vacuum. |
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Light can also be called... |
Radiant energy because it basically is radiation. |
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What do all kinds of light require? |
An original source of energy. Ex. Chemical energy Electrical energy Nuclear fusion |
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The first basic principle of light |
When light is absorbed it can become a different form of energy. |
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Light Energy > Chemical Energy |
Photosynthesis |
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Light energy > Thermal energy |
A black sweater in the sun. |
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Light Energy> Electrical Energy |
Solar panels. |
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Incandescent |
Gets hot - 95% of energy is released as heat The electricity turns to heat to light. |
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Fluorescent |
Electricity is absorbed by mercury particles >give off UV light> hits white phosphor and the phosphor particles give visible light. Expensive but energy saving. |
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Phosphorescent |
Same as fluorescent, but the electricity isn’t all released at once. Stays after. |
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Chemiluminescent |
Chemical reaction provides energy that is visible light. |
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Bioluminescence |
It’s chemiluminescence with living organisms. |
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Lighting Cost |
Total Cost= Power x Time x Price/Kw |
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How does light travel? |
Light travels in straight lines in all directions from its source until it strikes something. |
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Opaque |
No light can pass through the object,it can only be reflected or absorbed. |
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Translucent |
Some light is allowed to pass through. |
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Trans parent |
All light passes through reflected or absorbed. |
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Rough surfaces |
Reflect lines in many directions and create uneven angles. |
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Smooth surface |
Angles are all the same. |
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Law of reflection |
The angle of reflection is equal to the angle of incidence. |
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Angle of incidence |
Angle between incident ray and normal. |
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Angle of reflection |
Angle between the normal and reflected ray. |
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Convex mirror |
Mirrors that cave out and reflect images that look far away. |
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Concave mirror |
Mirrors that cave-in and make the image appear upside down. |
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Why does light bend? |
Light balance because it changes speed when it moves into a different density. |
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What happens when light moves into a more dense medium? |
The light bends towards the normal. |
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What happens when light moves into a less dense medium? |
The light will bend away from the normal. |
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Absorption |
The light is absorbed into an opaque object and changes into a different kind of energy. |
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Reflection |
Light hits a smooth and shiny surface and bounces off in a different direction. |
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Refraction |
Light travels through the transparent object and refracts. |
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Lens |
A curved piece of transparent that refracts the light as it passes through. |
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Concave lens |
It’s thinner in the middle than at the edges and diverges the light as it passes through. |
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Convex lens |
It is shaped like a teardrop and converges the light as it passes through, upside downing the image. |
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Lens in the Human eye |
Convex Lens |
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Lens in the Human eye |
Convex Lens |
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How can we see? |
The light enters the convex lens, and hits the retina. Then goes through the optic nerve to the brain to be interpreted. |
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Lens in the Human eye |
Convex Lens |
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The near point |
is the closest an object can be while it’s still in focus. 25 for adult seven for babies |
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Camera shutter |
Collects the light. The diaphragm limits the amount reaching the film. Similar to an iris. |
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What to human eye parts work together to control the amount of light |
The iris in the pupil control the amount of light entering the eye |
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Iris reflex |
When the iris adjusts the amount of light reaching the retina. |
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The film |
The film |
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What happens when light hits the retina? |
Electrical impulses travel to the brain to the optic nerve. |
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Humours |
Fluid that keeps the guy from collapsing and help refract light. |
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Blind Spot |
The location where the Optic Nerve and retina meet. There are no light cells. |
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Who invented the first telescope? |
Hans Lippershey |
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Who further developed the telescope? |
Galileo Galilei |
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How can we see? |
The light enters the convex lens, and hits the retina. Then goes through the optic nerve to the brain to be interpreted. |
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Refracting telescope |
It uses a convex lens to bend light. |
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Reflecting telescope |
Uses a concave mirror to bounce light. |
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The farther the image is away from the lens... |
The greater the magnification. |
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Binoculars |
Two reflecting telescopes shortened by prisms that reflect light. |
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Magnifying glass |
A simple type of microscope. |
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Who was able to see bacteria using a convex lens? |
Anton van Leeuwenhoek. |
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Four discoveries scientists made using microscopes. |
All living things have cells. Cell function and reproduction. Cancerous cells. Cells destroyed by viruses. |
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Metallurgist |
They see the size and shape of crystals with a microscope. |
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Refracting telescope |
It uses a convex lens to bend light. |
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Far Sighted |
They have trouble seeing close up the light rays are too long in terms of the retina and they can be fixed with a convex lens. |
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Camera Lens and convex lens |
Refracts light |
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camera film and retina |
Senses light |
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Camera focussing ring and ciliary muscles |
Method of adjustment for object distances |
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Diaphragm of camera and iris |
Controls opening for light entry |
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Camera aperture and pupil |
Opening for light entry |
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Accommodation |
When the ciliary muscles change the shape of the lens. |
