Light Flashcards
(19 cards)
Define luminous objects
Objects that produce and emit their own light
Examples of luminous objects
Sun,stars,flames
Define illuminated objects
Objects that do not produce their own light but reflects light
Examples of illuminated objects
Moon,buildings, and other shining objects
Explain how light travels
Light travels in a straight line
Explain how light leads to the formation of shadows
Light falls on opaque objects
The area behind objects become dark forming shadows
Explain how light leads to the appearance of the image (pin hole camera)
It works on the principle that light travels in a straight line
When an object is moved closer to the pin hole the image of the object becomes bigger
When the hole is made bigger the image of the object becomes brighter but blurred
Types of eclipses
Solar eclipse (sun)
Lunar eclipse (moon)
Describe the use to happen during solar eclipse
During solar eclipse the moon and the earth use to be in the same line from the sun
Therefore the moon will block the light from reaching part of earth
Name two points of shadows formed by the moon onto the earth
Umbra
Penumbra
Define umbra
Is the dark central part of the shadow (full shadow)
Define penumbra
Is the lighter outer part of the shadow (partial shadow)
Describe what use to happen during lunar eclipse (moon)
During lunar eclipse the earth and the moon use to be in the same line from the sun
Therefore the earth will block light from reaching part of the moon
Define transparent materials
Materials that allow light to pass through and the object on the other side are seen clearly
When light falls on transparent materials all of it passes through it
Examples of transparent materials
Diamond,water,air
Define translucent materials
Materials that allow some light to pass through, but some light is absorbed,reflected in different directions and the object on the other side is not seen
Examples of translucent materials
Some plastics and rectangular block
Define opaque materials
When light falls on opaque objects no light will pass through
Examples of opaque objects
Mirror and tree
