4-5.1 Summarize the basic properties of light (including brightness and colors).
Essential Question: What are the properties of light?
Textbook Pages: 300-303
Properties of Light
Brightness
● Related to the amount of light being seen
● Refer back to the Light Experiment and what we learned about light
Colors
● A prism is an object that separates white light into bands of colored light (red,
orange, yellow, green, blue, indigo, and violet).
● White light is made up of all colors of light mixed together.
Visible
● An object is visible if it gives off its own light or it reflects light
o The Sun, a candle flame, or a flashlight gives off its own light.
o The Moon reflects light
4-5.2 Illustrate the fact that light, as a form of energy, is made up of many
different colors.
Essential Question: Illustrate how light is made up of many colors.
Textbook Pages: 288-289
Light is a form of energy and is made up of many colors.
● Energy- the ability to make something move, happen, or change
● Colors- red, orange, yellow, green, blue, indigo, violet
o Each color of the spectrum represents a different amount of energy
Image from: ​
http://science.hq.nasa.gov/kids/imagers/ems/visible.html
4-5.3 Summarize how light travels and explain what happens when it strikes an
object (including reflection, refraction, and absorption).
Essential Question: Explain what happens with light strikes an object.
Textbook Pages: 290-293 and 304
Light travels in a straight line. The way that light reacts when it strikes the object
varies with the object.
Reflection
● When light is ​
reflected​
, it bounces back from a surface.
● Reflection allows objects to be seen that do not produce their own light.
● Examples:
o Light from the Sun strikes the Moon, some of the light reflects off the
Moon and can be detected by eyes.
o Light strikes a mirror or pool of water, it is reflected so that a reflection
can be seen of the object.
Refraction
● When light is ​
refracted​
, it passes from one type of transparent material to
another and changes direction.
● Examples:
o Light travels through a magnifying glass, it changes direction, and we see a
larger view of the object.
o A straw is viewed in water, light passes from the water to the air causing
the path of the light to bend. When the light bends the straw appears bent.
Absorption
● When light is ​
absorbed​
, it does not pass through or reflect from a material. It
remains in the material as another form of energy.
● Objects reflect the color that we see and absorb all others.
o Example: A red tomato reflects ONLY red light and absorbs all the rest.
4-5.4 Compare how light behaves when it strikes transparent, translucent, and
opaque materials.
Essential Question: What can light pass through?
Textbook Pages: 294
If an object is in front of light rays, several things can happen…
● If the object is ​
transparent​
,​
all​
of the light rays can pass through it.
o Objects can be seen clearly when viewed through transparent materials.
o Air, glass, and water are examples of materials that are transparent.
● If the object is ​
translucent​
,​
some​
of the light rays can pass through it.
o Objects appear as blurry shapes when viewed through translucent materials.
o Waxed paper and frosted glass are examples of materials that are translucent.
● If the object is ​
opaque​
,​
none​
of the light rays can pass through it.
o Wood, metals, and thick paper are examples of materials that are opaque.