The Electromagnetic Spectrum: Pages 53 and 54 QUESTION: What is a spectrum? OBJECTIVE: Students will be able to name and give a common use of waves that make up the electromagnetic spectrum. VOCABULARY: spectrumelectromagnetic spectrum

The Electromagnetic Spectrum Write these questions onto pages 53 and 54 SKIP ONE LINE BETWEEN EACH QUESTION 1.What is the relationship between the frequency of a wave and its energy? (Skip three lines) 2.What is a common use of these waves: radio waves, microwaves, infrared rays, ultraviolet rays, x-rays and gamma rays? 3.What basic colors makeup visible light?

What is the Electromagnetic Spectrum?Electromagnetic Spectrum The electromagnetic spectrum is a range of waves.electromagnetic spectrum The electromagnetic spectrum arranges waves from the lowest frequency to the highest frequency. DRAW AND LABEL THE SPECTRUM

THE HIGHER A WAVES FREQUENCY, THE GREATER ITS ENERGY

Waves of the Electromagnetic Spectrum There is one kind of electromagnetic wave we can see. Visible light waves Most electromagnetic waves are invisible. infrared rays microwaves ultraviolet waves X-rays radio waves gamma rays

Radio Waves Radio waves have the lowest frequency and longest wavelength of any wave Radio waves carry radio and television signals from the station to our homes

Microwaves Microwaves have many uses. Microwaves not only can be used to quickly heat food, but they are also used to carry cell phones signals and by police in their speed guns.

Infrared Rays Infrared rays are felt by us as heat. Much of the energy from the Sun reaches Earth as infrared rays.Sun reaches Earth as infrared rays. Special infrared cameras can show the heat being given off by objects. Hotter objects are shown as lighter colors and cooler objects are shown as darker colors.

Visible Light A very small part of the electromagnetic spectrum is able to be seen by humans. Only visible light can be seen by us. White light is really a mixture of all the colors of the spectrum. A piece of glass called a prism can separate white light into the colors of the spectrum.

Ultraviolet Rays Ultraviolet rays mostly come to us from the Sun. Small amounts of ultraviolet rays help our bodies produce vitamin D, but too many of these rays can cause sunburn, skin cancer and eye damage.

X-Rays X-rays have high frequencies. They carry enough energy to go through most matter. Because x-rays can go through most matter, they are used by doctors to look at bones inside the body. X-rays cannot go through bones or metal.

Gamma Rays Gamma rays have the highest frequencies of any waves. These rays are given off by distant stars. Fortunately, these our atmosphere filters out these rays before they reach Earth. Gamma rays carry so much energy that they are extremely dangerous. Gamma rays are used to kill cancer cells in the body.

The Electromagnetic Spectrum: p. 53, 54 Check that the answers to these questions are in your notes. 1.What is the relationship between the frequency of a wave and its energy? 2.What is a common use of these waves: radio waves, microwaves, infrared rays, ultraviolet rays, x-rays and gamma rays? 3.What basic colors makeup visible light?

VOCABULARY Spectrum- a range of related objects. Electromagnetic Spectrum- a complete range of electromagnetic waves in order from lowest frequency to highest.