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Light!. Before we begin…. Our class time in here will be similar to when we had the animals: we will need to direct our attention to the SmartBoard first, then break off into stations and activities. There will be no science journals!
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Before we begin… • Our class time in here will be similar to when we had the animals: we will need to direct our attention to the SmartBoard first, then break off into stations and activities. • There will be no science journals! • If you choose not to cooperate you will be answering questions from books at the front or worksheets with the science textbook.
What questions do we have about light and electricity? • Write a question on a slip of paper and put it in our question box. • We will draw 2 questions each day to answer.
What is light? • Light is a form of ENERGY. - Energy is the ability to make something move, happen or change.
What is light? • Light is made up of many different COLORS. - The different colors appear when white light is passed through a prism separated into a spectrum. - The colors represent different amounts of energy.
Types of light Visible light is the light that humans can see. Other animals can see different types of light. Dogs can see only shades of gray and some insects can see light from the ultraviolet part of the spectrum. The key thing to remember is that our light is what scientists call visible light. In order for an object to be visible, it must either: 1. Give off its own light ( sun, candle, flashlight) OR 2. REFLECT light
Seeing light The visible light you see is the light that is NOT absorbed by objects. Green plants for example, are green because they absorb all of the colors of the visible spectrum EXCEPT the green color.
Review Study Jams Clip • http://studyjams.scholastic.com/studyjams/jams/science/energy-light-sound/light.htm
Today we will: Separate sunlight into the colors of the spectrum! You need: Pencil Jacket Prism “Prism Play” Sheet
A transparent material allows light to pass through it because it is not absorbed or reflected. • Objects can be seen clearly when viewed through transparent materials. Air, glass, and water are examples of materials that are transparent.
examples Water allows light to pass through easily. Light passes through air clearly. Light bulbs are made of glass
A translucent material scatters or absorbs some of the light that strikes it and allows some of the light to pass through it. • Objects appear as blurry shapes when viewed through translucent materials. Waxed paper and frosted glass are examples of materials that are translucent.
Wax paper does not let light pass through easily. Frosted glass does not let light pass through easily.
An opaque material does not allow light to pass through, light is either reflected from or absorbed by an opaque material. Wood, metals, and thick paper are examples of materials that are opaque.
Light cannot pass through wood like a baseball bat. Light cannot pass through a football. Light cannot pass through Cocky.
Light’s Primary Colors • The human eye recognizes color using photo receptors called cones, which are located in the retina of each eye. • There are 3 types of cones that are each sensitive to 1 of the 3 primary colors of light – red, blue, green.
Light’s Primary Colors Red Blue Green (NOT Yellow)
Today we will… • Rotate at two different stations: One will be using the primary colors of light with flashlights and the “Colortime Theatre” worksheet. The other will be identifying opaque, translucent, and opaque materials using a flashlight as a source of light and recording your findings.
Combining the primary colors of light produces… Cyan Yellow Magenta http://www.teachersdomain.org/asset/lsps07_int_lightpigment/
How light strikes objects • When light hits an object, the light will either: • bounce off (reflection), • change direction (refraction), or • not reflect or pass through (absorbed). • http://www.kids-science-experiments.com/cat_absorption.html
Reflection • When light is reflected, it bounces back from a surface. • Reflection allows objects to be seen that do not produce their own light.
Reflection • When light strikes a smooth, shiny object, a mirror, or a pool of water, it is reflectedso that a reflection can be seen that looks very similar to the object seen with light reflected directly from it.
Refraction • When light is refracted it passes from one type of transparent material to another, and changes direction. For example, when light travels through a magnifying glass, it changes direction, and we see a larger, magnified view of the object.
Refraction • When a pencil 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 pencil appears distorted (bent or broken)
Absorption • When light is absorbed itdoes not pass through or reflect from a material. It remains in the material as another form of energy. • The colors of objects are determined by the light that is not absorbed but is reflected by the objects. • All other colors of light striking the object are absorbed by the object. • A red object, for example, reflects red colors of light and absorbs all other colors.
http://studyjams.scholastic.com/studyjams/jams/science/energy-light-sound/light-absorb-reflect-refract.htmhttp://studyjams.scholastic.com/studyjams/jams/science/energy-light-sound/light-absorb-reflect-refract.htm
