Introduction

1. Introduction Electromagnetic Spectrum

2. Key words to understand • Electromagnetic spectrum • Radio waves • Microwaves • Infrared Light • Visible Light • Ultraviolet light • X-rays • Gamma Rays • Photon • Wavelength • Frequency

3. What is a Photon? • Albert Einstein (1879-1955) proposed that light and all electromagnetic radiation consists of packets of energy. We now call this energy photons. • These Photons travel in waves and sometimes as particles. For us lets think of waves.

4. How do waves (photons) travel? • Think about a water wave….water waves have hills and valleys crest and troughs • All energy in the electromagnetic spectrum travel as waves (particles). Each spectrum has a different wavelength. • Different wavelengths represent different energy levels and as light can produce different colors

5. What is the EM Spectrum? • The electromagnetic (EM) spectrum is the range of all types of radiation. Radiation is energy that travels and spreads out as it goes ….these are the packets of energy that we previously called photons • The visible light that comes from a lamp in your house and the radio waves that come from a radio station are two types of electromagnetic radiation. • The other types of EM radiation that make up the electromagnetic spectrum are microwaves, infrared light, ultraviolet light, X-rays and gamma-rays.

6. The EM SPECTRUM • Each form of radiation has a use of effect on humans Weak end Strong end ROY G BIV

7. Connection to Astronomy • Light or radiation comes from the sun and other stars. Our sun is a star. • There are 7 types of radiation that are produced by stars and each of these have a different type of strength and wavelength. • What are the 7 types of radiation that are produced by stars? (hint we just talked about it)

8. 7 types of radiation in detail • Radio waves- weakest waves they go right through you. Used in stereos, televisions, and satellites • Microwaves- Used in special ovens to cook food and by cell phones • Infrared Light- Light we feel as heat, used by restaurants to keep the food warm • Visible light- only type of light we can see. RoyGBiv • Ultra violet light- light that can cause sunburns and too much of it can cause cancer • X-rays- light that is used by doctors to see into the body. They are so strong they pass through the skin but are stopped by the bones. Too much exposure can be bad • Gamma Rays- strongest and most dangerous. Found in the core of the sun and in explosions of nuclear bombs, exposure can mean death.