DO
STOP
WORK
 Finish
 Begin
collecting lab data.
to explain the observations you made
during the lab.
 Physics
 SLC
Club today
Thursday
 Answer
Sheets
 Missing
Polarization Lens
 Let’s
 Go
finish collecting our lab data.
to your last station.
Take out your “What is light” lab
 Emission
 Transmission
 Reflecting/Scattering
 Absorption
 Dispersion
 Polarization
 Diffraction
A
light bulb emits visible light; the energy of
the light comes from electrical potential
energy supplied to the light bulb.
 Some
forms of matter, such as glass or air,
transmit light, which means allowing it to
pass through.
 Light
can bounce off matter leading to what
we call reflection (when the bouncing is all
in the same general direction) or scattering
(when the bouncing is more random).
 When
you place your hand near an
incandescent light bulb, your hand absorbs
some of the light, and this absorbed energy
warms your hand.
These bananas absorb all
colors of light except
yellow. Instead yellow is
scattered, so the bananas
appear yellow!
 What
is emission?
 What
is transmission?
 What
is reflecting/scattering?
 What
is absorption?
 When
white light travels through a prism it
disperses into a rainbow, showing that white
light is made up of all the color we can see.
 When
light passes through a polarizing filter
it is only allowed to vibrate in one direction.
 Light cannot pass through two polarizing
filters that are set 90 degrees from one
another.
 When
a wave
encounters an
obstacle, or a slit
is diffracts and a
pattern is
produced on a
screen.
 What
is dispersion?
 What
is polarization?
 What
is diffraction?
 Jump
to “Details of light properties”
PowerPoint
 How
does light behave like a particle?
 How
does light behave like a wave?
 Wave-Particle
Duality says that light
exhibits both wave and particle properties.
This duality addresses the inability of
classical concepts like “particle” and “wave”
to fully describe the behavior of light.
 This
is a central concept in quantum
mechanics.
A
photon is one particle of light that obeys
the wave-particle duality of light.
Wave-particle duality
 Photons always want to travel at the speed of
light in a vacuum:


Every photon has a specific frequency and
wavelength that obey the equation:


f is the frequency of the photon (Hz)
Lambda is the wavelength of the photon (m)
 Photons


have energy that obey the equation:
h is Planck’s constant:
E is the energy measured in Joules (J)
 Note:
Not every photon has the same energy
 Explain
Heisenberg’s
uncertainty principle.
DO
STOP
WORK
 Solve
for the velocity, wavelength,
frequency, energy, and type of light.
 Remember
your long answers are due
tomorrow.

I’ll be collecting the them so write your answers
in the question packet too.
 Does
anyone have the completed letter slip?
 For
a photon that has wavelength of 650nm
find its velocity, frequency, energy, and
color.
 Velocity:

The velocity of a photon is always the same in a
vacuum.
 Frequency
of the photon:
 Energy
 Or:
of the photon:

Color of the photon

RED!
Which has a larger wavelength, red or blue light?
 Red

Which has a greater frequency, red or blue light?
 Blue

Which has more energy, red of blue light?
 Blue

 What
color light has a wavelength of 200nm?
 Gamma
Rays, X-Rays, Ultraviolet, Visible,
Infrared, Microwaves, and Radio Waves are
all part of the electromagnetic spectrum.
 They are all electromagnetic rays
 We
can only detect visible electromagnetic
waves with our eyes, but this doesn’t mean
the visible waves are a different type of
wave than the ones we can’t see.

How can chicken wings be used as an analogy for
the electromagnetic spectrum?








Spicy Cajun Style
Spicy Glazed
Baked Buffalo
Sesame
Maple
Broiled Barbecued
Inferno
Plain
TV, FM, AM, Wifi, cell phones
 Wavelength – Football field to a baseball
 Can you hear radio waves?


“Most people associate the term radio with sound,
but radio waves are a form of light with long
wavelength-too long for our eyes to see. Radio
stations encode sounds as electrical signals and
broadcast the signals as radio waves. What we call “a
radio” in daily life is an electronic device that
receives these radio waves and decodes them to recreate the sounds played at the radio stations.”-The
Cosmic Perspective
 Microwaves


Microwave oven, Radar
Wavelength – Lacrosse ball to a small dot
 Infrared


People, light bulbs
Wavelength – Cell to bacteria
 Visible


The only electromagnetic waves we can see
Wavelength – 780nm to 380nm
 Ultraviolet


The cause of sunburn
Wavelength – Virus to a protein



X-Ray machines
Wavelength – Protein to a water molecule
What could you see with X-ray vision?

“The “X-rays” that the doctor or dentist holds up are not
a form of light; they are just pieces of film. The images
of your bones and teeth are made with the help of a
special machine that works somewhat like the flash on
an ordinary camera but emits x rays instead of visible
light. This machine flashes the x rays instead of visible
light, and the x rays that are transmitted through your
body are recorded on film. Thus, what you see is the
image left by these x rays, not the x rays themselves” The Cosmic Perspective



Radioactive elements
Wavelength – Water molecule to even smaller
Is all radiation dangerous?


Many people associate the word radiation with danger.
However, the word radiate simply means “to spread out
from a center” (radius-radiation). Radiation is energy
being transmitted through space.
High-energy forms of radiation, such as particles from
radioactive materials or x rays, are dangerous because
they can penetrate body tissues and cause cell damage.
Low energy forms of radiation, such as radio waves, are
usually harmless.
 How
much more do you think we could learn
about the universe if we could see the full
electromagnetic spectrum?
 Find
the wavelength,
energy, and type of
radiation of a EM wave
that has a frequency of
13x10^13Hz.
DO
STOP
WORK
 Better
your understanding of the proper way
to answer Regents long answer questions.
 Practice
your skills of the electromagnetic
spectrum.

Index of Refraction Lab
Ryan
Matt O
Caleb
 Cody




What is Light? Lab – Lab quality!




Ryan
Matt O
Caleb
Meghann, and Annika
 Please
pass up your signed slips.
 Please
pass up your completed answer
packet.
 Let’s
go over the packet.
 One
worksheet, front and back
 Electromagnetic spectrum practice