waves of the electromagnetic spectrum eq: what is the electromagnetic spectrum?

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Waves of the Electromagnetic Spectrum EQ: What is the electromagnetic spectrum?

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Page 1: Waves of the Electromagnetic Spectrum EQ: What is the electromagnetic spectrum?

Waves of the Electromagnetic Spectrum

EQ: What is the electromagnetic spectrum?

Page 2: Waves of the Electromagnetic Spectrum EQ: What is the electromagnetic spectrum?

Vocabulary

• Electromagnetic Spectrum– Range of electromagnetic waves when they

are ordered by increasing frequency– Remember all EMW travel at the same speed,

but they have different wavelengths and frequencies

• As the wavelength decreases, the frequency increases

• The amount of energy carried by EMW increases as its frequency increases.

EQ: What is the electromagnetic

spectrum?

Page 3: Waves of the Electromagnetic Spectrum EQ: What is the electromagnetic spectrum?

Electromagnetic Spectrum

• Made up of 7 different types of waves

EQ: What is the electromagnetic

spectrum?

Page 4: Waves of the Electromagnetic Spectrum EQ: What is the electromagnetic spectrum?

Radio Waves - EMW with longest wavelengths and lowest frequencies

Can travel through a vacuum but most of our radio waves travel through air.

1. Antennas pick up radio waves from the air.

2. Then the radio waves go to the wires in your radio

3. The radio converts the EMW into sound that comes out your radio

EQ: What is the electromagnetic spectrum?

Page 5: Waves of the Electromagnetic Spectrum EQ: What is the electromagnetic spectrum?

Microwaves – shorter wavelengths and higher frequency

Microwave ovens and cell phones most common use

EQ: What is the electromagnetic

spectrum?

Page 6: Waves of the Electromagnetic Spectrum EQ: What is the electromagnetic spectrum?

Cell Phones–a transmitter and a

receiver

–cell phones depend on an overlapping network of cells, or areas of land several kilometers in diameter

–cell tower in the center of “cell” receives and sends microwaves

EQ: What is the electromagnetic spectrum?

Page 8: Waves of the Electromagnetic Spectrum EQ: What is the electromagnetic spectrum?

Infrared Waves

Give off heat – heat lamp, electric stove, toaster. Humans can sense it

Have shorter wavelengths and higher frequencies than radio waves

Infra means below – below red on the color spectrum

EQ: What is the electromagnetic spectrum?

Page 9: Waves of the Electromagnetic Spectrum EQ: What is the electromagnetic spectrum?

Infrared Waves

Thermogram – pictures taken by infrared camera. Shows regions with different temperatures with different colors– Used to detect motion of

clouds, growth of plants EQ: What is the electromagnetic

spectrum?

Page 10: Waves of the Electromagnetic Spectrum EQ: What is the electromagnetic spectrum?

Visible Light

• The light we can see

• Longest wavelength of visible light are red, shortest is purple

• Rainbow or prism refracts, or bends the light waves to produce different colors

EQ: What is the electromagnetic

spectrum?

Page 11: Waves of the Electromagnetic Spectrum EQ: What is the electromagnetic spectrum?

Visible Light

• Waves

EQ: What is the electromagnetic

spectrum?

Page 12: Waves of the Electromagnetic Spectrum EQ: What is the electromagnetic spectrum?

Ultraviolet Rays

• UV rays

• Ultra is Latin for beyond, so these waves are just beyond the color violet

• Carry more energy than visible light because they travel at a higher frequency

EQ: What is the electromagnetic

spectrum?

Page 13: Waves of the Electromagnetic Spectrum EQ: What is the electromagnetic spectrum?

Ultraviolet Waves

UV lamps used to kill bacteriaUV waves help produce vitamin D in the body, cause sunburnHelp newborns who have jaundice

EQ: What is the electromagnetic spectrum?

Page 14: Waves of the Electromagnetic Spectrum EQ: What is the electromagnetic spectrum?

X - Rays

• Carry more energy than UV rays because of their higher frequency

• Can penetrate most matter with the exception of bone and lead. These are too dense

EQ: What is the electromagnetic

spectrum?

Page 15: Waves of the Electromagnetic Spectrum EQ: What is the electromagnetic spectrum?

Gamma Rays

• Shortest wavelength and highest frequency

• Used in radiation therapy to kill cancer cells

• Examine body’s internal structure

Supernova

EQ: What is the electromagnetic spectrum?

Page 16: Waves of the Electromagnetic Spectrum EQ: What is the electromagnetic spectrum?

Class Work and Homework

• Fill In – What did I learn– Confused– Say

– Read pages 79– 86– Electromagnetic spectrum jumble– questions 1-6 and page 87 “Are cell phones

harmful?”

EQ: What is the electromagnetic

spectrum?