Electromagnetic Waves Chapter 17 Section 1-2 Pages 532-547.

Electromagnetic Waves

Chapter 17

Section 1-2

Pages 532-547

What are electromagnetic waves?

Special kind of transverse wave Does NOT need to pass through a medium

Can travel through empty space

What are electromagnetic waves?

Velocity in empty space = 300,000,000 m/sLow wavelength and High frequencyHigh wavelength and Low frequencyYou can use v = λ • f

Wavelengths can be arranged into a spectrum Frequency relates to the amount of energy

What is the electromagnetic spectrum?

A – Radio Waves Large wavelength, low frequency Low energy Used for AM radio, short wave radio, FM radio,

cell phone, cordless phone, TV, radar, microwave Microwaves are high energy radio waves


B – Infrared Radiation Heat radiation – warm objects give off more radiation Thermogram – used to see heat radiation in body, can help

locate tumors which give off more heat radiation Night vision goggles – use infrared radiation to detect

targets


C – Visible Radiation = Light Smallest range of the E.M. spectrum The only part of the E.M. spectrum we can see White light can be broken down into a color spectrum by

using a prism ROY G. BIV RedRed, , OrangeOrange, , YellowYellow, , GreenGreen, , BlueBlue, , IndigoIndigo, , VioletViolet


C – Visible Radiation = Light Photosynthesis – plants use light energy in order to

create their own food Human eye – chemical reactions in eye that let you

see are stimulated by light


D – Ultraviolet Radiation (UV) UV rays help skin cells produce vitamin D for

healthy bones and teeth But too much UV radiation kills healthy cells UV radiation can lead to dry, sagging skin, even

skin cancer


D – Ultraviolet Radiation (UV) Earth’s atmosphere – ozone layer (O3) deflects

harmful UV rays from Earth Chlorofluorocarbons destroy ozone molecules and

reduces Earth’s defense against UV rays


E – X-Rays X-Rays contain more energy and penetrate more easily X-Rays pass through skin and muscle, but are absorbed by

dense bone matter and can be used to take a “picture” of bones

Too much exposure to X-Ray radiation can be harmful


F – Gamma Rays Highest frequency in the E.M. spectrum Have the most energy, can penetrate most things Emitted from the nuclei of radioactive atoms, also

can be received from space Used to kill cancer cells during radiation therapy,

but healthy cells are often killed or damaged too


Which is true? A. high wavelength high energyB. high frequency high energy


Which is true?

B. high frequency high energy


X-Rays have less energy than….A. Radio WavesB. InfraredC. Visible LightF. Gamma Rays


X-Rays have less energy than….

F. Gamma Rays


Which is the smallest part of the electromagnetic spectrum? A. Radio Waves B. Infrared Radiation C. Visible Light D. Ultraviolet Radiation E. X-Rays F. Gamma Rays


Which is the smallest part of the electromagnetic spectrum?

C. Visible Light


Which part of the electromagnetic spectrum has the smallest wavelength? A. Radio Waves B. Infrared Radiation C. Visible Light D. Ultraviolet Radiation E. X-Rays F. Gamma Rays


Which part of the electromagnetic spectrum has the smallest wavelength?

F. Gamma Rays


Which part of the electromagnetic spectrum has the smallest frequency? A. Radio Waves B. Infrared Radiation C. Visible Light D. Ultraviolet Radiation E. X-Rays F. Gamma Rays


Which part of the electromagnetic spectrum is used to detect broken bones? A. Radio Waves B. Infrared Radiation C. Visible Light D. Ultraviolet Radiation E. X-Rays F. Gamma Rays


Which part of the electromagnetic spectrum is also known as heat radiation? A. Radio Waves B. Infrared Radiation C. Visible Light D. Ultraviolet Radiation E. X-Rays F. Gamma Rays


Which part of the electromagnetic spectrum is needed for healthy bones, but only in small quantities? A. Radio Waves B. Infrared Radiation C. Visible Light D. Ultraviolet Radiation E. X-Rays F. Gamma Rays


High frequency Radio Waves are known as….A. Short wavesB. Gamma raysC. Visible lightD. Microwaves

Electromagnetic Waves

Chapter 17

Section 1-2

Electromagnetic Waves Chapter 17 Section 1-2 Pages 532-547.

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Transcript of Electromagnetic Waves Chapter 17 Section 1-2 Pages 532-547.