ch37_kbrl

37.1 · The making of voltage is based on the relative motion between the conductor and the magnetic field. · ** Electromagnetic Induction **: inducing voltage by changing the magnetic field around a conductor · The larger the number of loops of wire that go in a magnetic field, the bigger the induced voltage and current will be in the wire · Fast motion makes a greater voltage. 
 * Chapter 37: Electromagnetic Induction**



37.2 · ** Faraday's Law **"The induced voltage in a coil is proportional to the product of the number of loops and the rate at which the magnetic field changes within these loops.” ·  The total current made by electromagnetic induction also depends on the resistance of the coil and the circuit its connected to ·  ** Example: ** you can throw a magnet in and out of a blocked rubber loop and in and out of a closed loop of copper. The voltage will be the same for both · The bonding for the copper and rubber to the permanent atoms stops movement of charge that happens so open in the copper one

37.3 · If one part of a magnet is blocked in and out of a wire coil then the induced voltage changes direction · When the magnetic field force weakens then the voltage is induced in the opposite direction · ** Generator: ** Rotating the coil in a stationary magnetic field

· A generator is the opposite of a motor · A motor switches electrical energy into mechanical energy <span style="font-family: Symbol; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol; msofareastfontfamily: Symbol; msobidifontfamily: Symbol; msolist: Ignore;">· A generator switches mechanical energy into electrical energy <span style="font-family: Symbol; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol; msofareastfontfamily: Symbol; msobidifontfamily: Symbol; msolist: Ignore;">· The voltage made by the generator changes and the current formed is changing alternating current (ac) <span style="font-family: Symbol; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol; msofareastfontfamily: Symbol; msobidifontfamily: Symbol; msolist: Ignore;">· The current sometimes changes magnitude and direction <span style="font-family: Symbol; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol; msofareastfontfamily: Symbol; msobidifontfamily: Symbol; msolist: Ignore;">· The average alternating current in the United States changes its magnitude and direction during 60 series per second which is 60 hertz <span style="font-family: Symbol; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol; msofareastfontfamily: Symbol; msobidifontfamily: Symbol; msolist: Ignore;">· Big coils make many loops of wire wrap on an iron core, which makes a frame a lot like the frame of a motor <span style="font-family: Symbol; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol; msofareastfontfamily: Symbol; msobidifontfamily: Symbol; msolist: Ignore;">· The frame is linked on the outside to a turbine <span style="font-family: Symbol; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol; msofareastfontfamily: Symbol; msobidifontfamily: Symbol; msolist: Ignore;">· Energy from wind or falling water can be used to make the turbine work while most generators get power by moving steam

<span style="color: #21eda7; font-family: 'Times New Roman', Times, serif;">37.4 <span style="font-family: Symbol; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol; msofareastfontfamily: Symbol; msobidifontfamily: Symbol; msolist: Ignore;">· “Moving charges experience a force that is perpendicular to both the ir motion and the magnetic field they traverse” <span style="font-family: Symbol; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol; msofareastfontfamily: Symbol; msobidifontfamily: Symbol; msolist: Ignore;">· The redirected wire is the motor result and the law of induction is the generator result

<span style="color: #ffff00; font-family: 'Times New Roman', Times, serif;">37.5 <span style="font-family: Symbol; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol; msofareastfontfamily: Symbol; msobidifontfamily: Symbol; msolist: Ignore;">· The coil linked to the power source is the primary which is input and the other coil is the secondary which is output <span style="font-family: Symbol; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol; msofareastfontfamily: Symbol; msobidifontfamily: Symbol; msolist: Ignore;">· When the switch is stopped in the primary and current go’s through its coil a current also go’s in the secondary. <span style="font-family: Symbol; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol; msofareastfontfamily: Symbol; msobidifontfamily: Symbol; msolist: Ignore;">· When the primary is opened a flow of current registers in the secondary but go’s in the opposite direction <span style="font-family: Symbol; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol; msofareastfontfamily: Symbol; msobidifontfamily: Symbol; msolist: Ignore;">· The magnetic field is focused in the middle which go’s into the secondary <span style="font-family: Symbol; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol; msofareastfontfamily: Symbol; msobidifontfamily: Symbol; msolist: Ignore;">· The secondary catches more of the field change <span style="font-family: Symbol; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol; msofareastfontfamily: Symbol; msobidifontfamily: Symbol; msolist: Ignore;">· ** Transformer: ** is a device for increasing or decreasing voltage through electromagnetic induction

<span style="font-family: Symbol; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol; msofareastfontfamily: Symbol; msobidifontfamily: Symbol; msolist: Ignore;">· The relation that voltage will change is equal to the ratio of the amount of turns on the output coil to the number of turns on the input coil <span style="font-family: Symbol; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol; msofareastfontfamily: Symbol; msobidifontfamily: Symbol; msolist: Ignore;">· The full power controlled by the transformer is the same in both coils

<span style="color: #800080; font-family: 'Times New Roman', Times, serif;">37.6 <span style="font-family: Symbol; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol; msofareastfontfamily: Symbol; msobidifontfamily: Symbol; msolist: Ignore;">· Electric utilities provide power in the form of changing current <span style="font-family: Symbol; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol; msofareastfontfamily: Symbol; msobidifontfamily: Symbol; msolist: Ignore;">· Power can be carried from power plants to cities at 120000 volts or more <span style="font-family: Symbol; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol; msofareastfontfamily: Symbol; msobidifontfamily: Symbol; msolist: Ignore;">· Power is sends big distances at high voltages and also low currents

<span style="color: #11a7d4; font-family: 'Times New Roman', Times, serif;">37.7 <span style="font-family: Symbol; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol; msofareastfontfamily: Symbol; msobidifontfamily: Symbol; msolist: Ignore;">· The new version of Faraday’s Law: “An electric field is created in any region of space in which a magnetic field is changing with time. The magnitude of the created electric field is proportional to the rate at which the magnetic field changes. The direction of the created electric field is at right angles to the changing magnetic field.” <span style="font-family: Symbol; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol; msofareastfontfamily: Symbol; msobidifontfamily: Symbol; msolist: Ignore;">· If a charge is in a changing magnetic field then it will occur with a force from the electric field <span style="font-family: Symbol; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol; msofareastfontfamily: Symbol; msobidifontfamily: Symbol; msolist: Ignore;">· James Clark Maxwell made a complement to Faraday’s Law to guess the effect of change in an electric field <span style="font-family: Symbol; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol; msofareastfontfamily: Symbol; msobidifontfamily: Symbol; msolist: Ignore;">· “A magnetic field is created in any region of space in which an electric field is changing with time. The magnitude of the created magnetic field is proportional to the rate at which the electric field changes. The direction of the created magnetic field is at right angles to the changing electric field.”

37.8 ·   When an electric current is present it will generate a magnetic field but the changing magnetic field around a changing current will generate an electric field <span style="font-family: Symbol; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol; msofareastfontfamily: Symbol; msobidifontfamily: Symbol; msolist: Ignore;">· ** Electromagnetic Wave: ** a wave that is partly electric and partly magnetic and carries energy. Emitted by vibrating electric charges. <span style="font-family: Symbol; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol; msofareastfontfamily: Symbol; msobidifontfamily: Symbol; msolist: Ignore;">· Electromagnetic waves are changing electric and magnetic fields that go at the same rate and support each other <span style="font-family: Symbol; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol; msofareastfontfamily: Symbol; msobidifontfamily: Symbol; msolist: Ignore;">· The only pace waves can move is the speed of light