Light is an Electromagnetic Wave By Mackenzie Cottle, Hao Vuong, Gian Carlos, Zach Totah

The Speed of an EM Wave An Electromagnetic wave is energy in motion Most EM waves are invisible to humans, but still some can affect your body Sound waves and water waves travel by making matter movements Electromagnetic radiation depends on electric fields and magnetic fields An EM wave moves with a certain speed and has a certain wave length Gian

EM Waves in a Vacuum In a vacuum, EM waves all travel the same speed 300,000 kilometers per second, also known as the speed of light In calculations, this number is often referred to as the letter c It takes much less than a second for any EM wave to travel to any two points on earth The vast distances of space are often measured in units of light-years Gian

The Electromagnetic Spectrum The speed of EM waves in air is almost the same as it is in a vacuum Scientists use ideas of spectrum to describe the possible frequencies of EM waves, or the electromagnetic spectrum Wave lengths can be tens of kilometers or trillionths of a centimeter Different terms describe the different parts of the electromagnetic spectrum Hao: I am doing the electromagnetic Spectrum. Electromagnetic spectrum is the range of all electromagnetic frequencies. The speed of Em waves in air is almost the same as it is in a vacuum. Scientist used many ideas to describe the possible frequencies of Em waves, and one idea is spectrum. There are at least tens of kilometers or more of a centimeter in the wave length

Light Waves, Rays, and Particles A wave will spread out, or radiate, from a central source Electromagnetic Radiation is the energy that moves in the form of an EM wave EM radiation is produced as tiny bundles of energy called photons Matter absorbs light when it takes up the photons energy The higher frequency a photon has, the more energy it will have Hao

Ultraviolet, Gamma, and X-Rays Type of Radiation Positive effects Negative effects Ultraviolet: light that is used in hospitals, ponds, etc. Can be used to sterilized medical tools and food Can kill living cells and causes a high percent chance of cancer Gamma: radiation very harmful to skin Can detect nuclear explosions in space Has a large amount of radiation given off X-Rays: used in hospitals, electronics, etc. Searches for broken bones and tumors Can kill living cells and damage body Mackenzie Electronics in X-RAY: used to see if melted points are put together well

Radio waves and Microwaves Radio waves are produced easily by varying an electric current in a wire EM waves can travel long distances without losing energy Radio waves carry information in long distances, also used in radio broadcasts Radio waves of higher frequencies are also called microwaves, cell phones and other technology use this Microwaves bounce off of many surfaces Molecules tend to absorb waves (microwave sends energy to food) Zach

Infrared Radiation IR (Infrared Radiation) waves are easily given off and absorbed by solids, liquids, and some gases Cannot be seen, but can be felt as heat Most objects on earth are giving off radiation in low frequencies The high frequencies near visible light range are called near-IR EM spectrums that humans can pick up are called visible light The range is small, so small that only half of the radiation from the sun that reached the ground is visible light Zach