# Phy

 What is the electromagnetic spectrum? The classification of electromagnetic waves acccording to frequency. (In a vacuum, all electromagnetic waeves move move at the same speed differing only in frequency. What are electromagnetic waves? What are they made of? A larger group of energy.It is the vibrating electric and magnetic fields that are regenerating each other to make up an electro.wave. A LONGER WAVE LENGTH IS ASSOCIATED WITH A HIGHER/LOWER FREQUENCY. A LONGER WAVE LENGTH IS ASSOCIATED WITH A LOWER FREQUENCY. LONGER-LOWER ORDER OF THE SPECTRUM RADIO WAVESMICRO WAVESINFRA-RED WAVESVISABLE LIGHTULTRA VIOLETXRAYSGAMMA RAYS ELECTROMAGNETIC INDUCTION Def1: The induction of voltage when a magnetic field changes with time. If the magnetic field within a closed loop changes in any way, a voltage is induced in the loop.Def2: The phenomenom by which a current is induced in a conductor due to change in the magnetic field near the conductor is known as electromagnetic induction. What is INDUCED current? The current obtained due to the relative motion between the coil and the magnet is called induced current. Electromagnetic induction. The electromagnetic waves consists of two perpendicular fields: ___, ____. Electric fieldMagnetic Field All wave lengths have the same... speed Reemision Defintion Absoprtion def Re-emission: light reflected back from a surfaceopp of Absorption What happens to the electrons and their energy when light is reemitted (reflected)? The atoms or molecules in the material holds the energy for less time, with less change of collision w/ neighboring atoms and molecules. Less energy is trtansformed as heat.Instead, energy is wasted on light remission. Most tihngs around us are ___. Meaning, they absorb light without remission (reflecting). OPAQUE Energetic vibrations does what to thermal energy? Increase temp. of material Why are metals shiny? Metals have loose free outer electrons. When light sines on metal and set these free electrons into vibration, their energy does not "spring" from atom to atom--it is reflected instead.With each bounce, comes absorption.On dry surfaces, it bounces right back to the eye. Whearas in wet surfaces, more is absorped. What is reflection? The return of light rays from a surfaceEnergized electrons re-emit the light we see on each page. White- reemits all visible frequenciesBlack- Absorbs all visible frequencies law of reflection how do you measure the angle of reflection equals the angle oc incidence (pool table). measure them from a perpendicular line to the plane of the relfecting surface law of reflection diffuse reflection reflecting surfaces are irregular, light is returned in irregular directionsrough surfacemost of our env. seen by this kind REFRACTION UNLESS LIGHT IS PERP. TO THE SURFACE OF PENETRATION, BENDING OCCURS REFRACTION COLOR WITH LOWEST FREQ. AND WITH HIGHEST LOWEST-REDHIGHEST-VIOLET EMITTING PRODUCE AND DISCHARGE, MAKE Why do objects seem a certain color? Objects around us reflect only part of the light that is incident upon them, thae part that provides their color Ex A red rose has the ability to reflect red light but cannot reflect other colors. PIGMENTS fine particles that selectively absorb light of particular frequencies and selectively transmit others. Transmission: If the object is transparent, then the vibrations of the electrons are passed on to neighboring atoms through the bulk of the material and reemitted on the opposite side of the object. DISPERSION DEF The serperation of light into colors arranged by frequency. Polarization The alignment of the transverse electric vectors that make up electromagnetic radiation. Such waves of aligned vibrations are said to be polarized. Gamma rays: They have very high energy and will even go through metals. FREQUENCY SPECIFIES THE NUMBER OF TO AND FRO VIBRATIONS IT MAKES IN A GIVEN TIME (USUALLY 1 SEC) The frequency of virbating electrons and the frequency of the wave produced are... the same What is a mirage? A mirage is a naturally occurring optical phenomenon in which light rays are bent to produce a displaced image. Light travels faster through the thinner hot air near the surace than through the denser cool air above. The result is upward bending. Refraction rather than reflection Light rays are bent to produce a displaced image of distant objects or the sky. Authorbettyvillagomez ID76172 Card SetPhy DescriptionStudy test 2 Updated2011-03-30T19:27:31Z Show Answers