RIGHT PAGE 42 October 11, 2012 Focus : Intro to Light

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RIGHT PAGE 42 October 11, 2012 Focus : Intro to Light Objective : I will be able to explain how light waves interacts with materials and analyze the eye / sight. EQ: How does scattering of light affect us? HW: project, ask someone you know the questions - PowerPoint PPT Presentation

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RIGHT PAGE 42 October 11, 2012Focus: Intro to LightObjective: I will be able to explain how light

waves interacts with materials and analyze the eye / sight.

EQ: How does scattering of light affect us?HW: project, ask someone you know the

questionsWarm-Up: Preview (answer these questions)Why is the sky blue? Why are clouds white?

RIGHT PAGE 42 October 11, 2012Focus: Intro to LightObjective: 6.P.1.2 I will be able to explain

how light is a form of energy and travels in transverse waves.

HW: write 5 test questions about waves and light, assessment tomorrow, parent sign, test corrections

Warm-Up: Read text pages C9 – C14Write a summary / gist of what you read

Waves are started by a force. Let’s look at a slinky. When you shake a slinky, it creates a wave. In this case, we created a force by moving the slinky.

Waves move away from the force.

Force Direction of the wave

When a force creates a wave, energy moves not matter. The force makes the atoms in the matter vibrate. The vibration causes them to bump into each other like dominoes, sending the wave down the line. But the matter itself stays in the same spot.

Transverse Waves:

In a transverse wave the matter in the wave moves up and down at a right angle (perpendicular) to the direction of the wave

The wave is moving away from the force.

The energy is moving up and down, perpendicular to the wave’s direction.

•Which direction is the energy in the wave going? [ (away from the moving hand) / (toward the moving hand) ]

•How can you tell? _______________________________________________________

•What is the medium for this wave? __________________________________________

•Which direction is the medium moving?_______________________________________

•What type of wave is this? _________________________________________________

SHOW WHAT YOU KNOW:

What is the second kind of mechanical wave?

Longitudinal Waves (Compression Waves)

In a longitudinal wave the matter in the wave moves back and forth parallel to the direction of the wave

In a longitudinal wave the matter in the wave moves back and forth parallel to the direction of the wave

The energy moves in the same direction as the wave.

•Which direction is the energy in the wave going? [ (away from the moving hand) / (toward the moving hand) ]

•How can you tell? _______________________________________________________•What is the medium for this wave? __________________________________________•Which direction is the medium moving?_______________________________________•What type of wave is this? _________________________________________________•Compared to the direction of the energy, the medium moved in what direction? __________________________________________________________

SHOW WHAT YOU KNOW:

Which wave travels faster?

Think-Pair-Share:• Think about the slinky

• Let’s find out!– Human wave activity

Since the energy is traveling the fastest way it can (in a straight line), the longitudinal wave is faster than the transverse wave. It gets from the force to the stopping point first. It is the first wave you feel in an earthquake.

The transverse wave takes more time and energy to go perpendicular to the direction of the wave. You feel this wave second in an earthquake. It is sometimes called the “aftershock”.

All about ?!What do these things have in common?

They all use light waves!

This is our boy, Roy.• Roy’s full name is Roy

G. Biv.• He’s got three younger

brothers: Radio, Micro and Infrared. He has to make money for his family.

Roy’s Brothers

At the end of today:You will be able to answer this question:

1. Label the electromagnetic spectrum below with the missing wave names.

2. Which wave has more energy – visible light or gamma rays?

Cornell NotesWhat is light? 

Why is a light a form of energy?

A type of energy that transfers waves.  Light is a form of energy because it has the ability to cause change. Energy is the ability to cause change.

Cornell NotesWhat are Electromagnetic Waves? 

Can all light be seen? 

Who is ROY G. BIV?

All light travels in the form of Electromagnetic Waves. Electromagnetic waves are light waves.  NO! We can only see some light with our eyes. This is called visible light.  ROY G. BIV is an easy what to remember the colors in visible light!

Electromagnetic Spectrum

Electromagnetic Spectrum

Electromagnetic Spectrum

A Prism breaks up visible light!

. light energy travels in waves, too. What makes one kind of light different from others is its wavelength - or range of wavelengths. Visible light includes the wavelengths our eyes can see. The longest wavelengths we can see look red to us. The shortest wavelengths we can see look blue or violet

Electromagnetic Spectrum

Another important thing to know about light is that it travels in a straight line unless something gets in the way to

reflect it (like a mirror) Refract it, bend it (like a prism)

or scatter it (like molecules of the gases in the atmosphere)

Your TurnTeach your partner about

Electromagnetic Waves! Tell them about:

•  Electromagnetic Waves• The different light waves in the

Electromagnetic Spectrum• ROY G. BIV

Quiz Your Partner!1. Which wave has more energy – Gamma

Rays or X-Rays?2. Which wave has less energy – Radio Waves

or Microwaves?3. Which wave has a higher frequency –

Ultraviolet Light or Infrared Light?4. Which wave has a lower frequency – Visible

Light or Gamma Rays?5. Which color has a lower frequency – Red or

Yellow?

Exit Ticket1. Label the electromagnetic spectrum below

with the missing wave names. 2. Which wave has more energy – visible light or

gamma rays?