CHAPTER ONE Waves All Around Toss a rock into a pond and watch the water ripple out from the center Listen to your favorite song as you stretch out to dry after a swim Waves surround you Some of them you can see Others are invisible to the eye Every day waves bring light and sound A wave is a disturbance that travels through matter or space It transfers energy from one place to another Waves transfer energy but they don’t carry matter 4
Waves are either electromagnetic or mechanical Scientists call light radiation electromagnetic radiation Light waves can travel through space The Sun is the main source of electromagnetic waves Under high heat and pressure the Sun’s fiery core reduces its mass creating electromagnetic energy 5
Light Energy Visible light arrives on Earth with the other kinds of waves on the electromagnetic spectrum That’s the light people see Most people think of visible light when talking about light waves The study of light waves is optics ELECTROMAGNETIC SPECTRUM RADIO WAVES MICROWAVES INFRARED RADIATION VISIBLE LIGHT ULTRAVIOLET RADIATION X-RAYS GAMMA RAYS 6
However visible light is only one kind of electromagnetic energy Each kind of light energy on the spectrum has a different-sized wavelength Waves like radio waves visible light microwaves x-rays and others line the electromagnetic spectrum Visible light 7
