Transcript What Wavelength Was That?

How do you LIGHT Up
your world ?
Part I-Virginia SOL 5.3
Examining Light 2004
with Hands-On Activities
Compiled by, Marjorie Anne Wallace
Elementary Science Resource Teacher
2002-2005 / NNPS & NSF Coop Agreement
Welcome to a power point
presentation on LIGHT.
• We will investigate the following:
• 1. What is light?
• 2.What are some sources of light around us?
• 3. What are opaque, transparent, & translucent
objects?
• 4. What is a light wave?
• 5.Are there any hands-on/minds-on activities I can
do to learn more?
LIGHT Standards
• National Science
Education Standards
• Physical Science:
Content Standard B
• As a result of the
activities in grades
K-4, all students should
develop an
understanding of light,
heat, electricity, and
magnetism.
• Virginia Standards of
Learning 5.3 a-e:
• The student will
investigate and
understand basic
characteristics of
visible light and how
it behaves. (*Key
concepts, 5.3a-e, are
listed in your teacher
curriculum guide)
Light
• Our primary source of light is the sun.
• Light travels in straight lines at a speed of
186,000miles per second.
• *Light waves travel faster than sound waves!
• Light energy from the sun travels through
space , reaches earth, and some of it turns to
heat energy and warms the earth’s air.
• Light from the sun also travels to the cells of
green plants (producers) and is stored as
energy.
• When light reaches an object, it is absorbed,
reflected, or passes through it.
Sensing Light
• Humans have two
light detectors.
• Do you know what
they are called?
How many sources of Light
can you list and explain?
• SUN=warms air,
water, and land.
• Fire=provides heat, light,
and cooking fuel.
• Lightning=
• Firefly=
• Flashlight=
• Light bulb=
• Laser beams=
• Optical
telephone
fibers=
*Traffic lights=
*AIMS: Primarily Physics:
Light Sources Activity
Can you answer these 5th grade
2003-SOL queries?
• 1. A person will see a flash of lightning before
they hear the thunder that goes with it because?
*SOL 2003 querie #14/CORE 1 Exam (5.3e)
• 2.Can you draw a long wavelength and a short
wavelength next to it? *SOL2003 queire #9/CORE 1 Exam(5.3a)
• 3.What scientific tools are used to study light?
*SOL2003/CORE 2 Exam(5.3b)
• 4. Can you contrast objects that are transparent,
translucent, and opaque? *SOL2003/CORE 2 Exam(5.3d)
“Just Passing Through:”
What happens when light strikes
glass? Or waxed paper? Or a book?
• If light travels through an
object it is =transparent
• If light is blocked by an
object and a dark
shadow is cast it is=
opaque.
• If some light passes
through but not all and a
light shadow is present it
is=translucent.
*AIMS:Primarily Physics: Just
Passing Through Activity
What happens when light
hits these objects?
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Glass of water
School bus window
Notebook paper
Waxed paper
Plastic wrap
Tissue paper
Cardboard
Textbook
Hand lens…
Transparent objects:
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The windows on a school bus,
A clear empty glass,
A clear window pane,
The lenses of some eyeglasses,
Clear plastic wrap,
The glass on a clock,
A hand lens,
Colored glass…
ALL of these are transparent.
Yes, we can see through them
because light passes through
each of them.
Translucent objects
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Thin tissue paper,
Waxed paper,
Tinted car windows,
Frosted glass,
Clouds,
All of these materials
are translucent and
allow some light to
pass but the light
cannot be clearly
seen through.
Opaque objects:
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Heavy weight paper,
Cardboard
Aluminum foil,
Mirror, bricks, buildings,
Your eyelids and hands,
Solid wood door,
All of these objects are
opaque because light
cannot pass through them
at all.
• They cast a dark shadow.
Let’s find out how light travels?
• Simple Activity: 1 working flashlight
• 1. Shine a flashlight on a wall.
• 2. Does light from the flashlight reach the
wall? How do you know?
• 3. What evidence do you have showing
light travels in a straight line?
• 4.Record answers in your science journal
• 5.Move closer with the flashlight.
• Any changes? *Write a story about light.
Understanding Waves
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The traditional hands-on/minds-on activities:
1. “slinky lab: A Wave Simulation!” as well as
2. “Waves in Action” (visual learner), and
3. “Act It Out!Waves Tall and Small” (kinesthetic
learner) activities will help children understand
waves better.
*Science Museum of Virginia: Light & Sound
www.smv.mus.va.us
• *Unitedstreaming movies:”Out of Darkness: An
Introduction to Light: Facts About Light.”(auditory
& visual learners). *Check with your building technology dept for
your schools password.
What is light really?
Electromagnetic radiation waves
• Light waves are three
dimensional.
• Light waves vibrate in all
planes around a center
line.
• The waves have high
points called “crests.”
• Waves also have low
points called “troughs.”
• *The distance from one
crest to the next crest is
called a “wavelength.”
• *The number of waves
passing a given point in
one second is called the
“frequency.”
wavelength
*A Science Museum of VA:
Light Science Activity
Notice the wavelength is long(Radio waves) and gets shorter (Gamma Rays)
A wave simulation:
*Science Museum of VA
A Wave Simulation
Activity/Demo OR
GEMS:”Invisible Universe”
Comparing Wave Makers
• Materials: 1 long spring or rope
• 1. Teacher and a strong student will hold either
end of the coiled spring tightly braced against
their body.
• 2.Teacher will walk away from the student until
the spring is loosely stretched between them.
• 3.Gently snap the spring up and down once to
send a wave of energy to the student’s hand. It
will bounce back, or reflect, from the stationary
end.
• 4. Point out each wave has a crest (high half) and
a trough (low half). Check for understanding
*Electromagnetic Radiation
• Electromagnetic radiation can be described as
a stream of photons. Each photon traveling in a
wave-like pattern, moving at the speed of light
and carrying some amount of energy.
• The only difference amongst radio waves,
visible light, and gamma-rays is the amount of
energy of the photons. Radio waves have
photons with low energies. Microwaves have a
little more energy than radio waves. Gammarays and cosmic rays have highest energy
waves and are the deadliest.
*Page info from NSTA Conference 2004
Don’t’ forget…longest waves (radio) ..to shortest waves (cosmic)
*Page info from NSAT Conference 2004
1.Acting It Out! Waves Tall & Small
Activity(The electromagnetic family)
+2.Scaling the Spectrum Activity
• Materials:
• 1. 9 volunteers
• 2. paper & pencil.
• These 2 activities help to
explain the
electromagnetic spectrum
and dispel some of the
common misconceptions.
*Science Museum of Virginia
Acting It Out! Activity +
Scaling the Spectrum Activity OR
GEMS: Invisible Universe
Comparing Wave Makers I.
Power point II covers the
electromagnetic spectrum!