Induced EMF Generators Transformers Physics 114 2192021 Lecture
![Induced EMF Generators , Transformers Physics 114 2/19/2021 Lecture VIII 1 Induced EMF Generators , Transformers Physics 114 2/19/2021 Lecture VIII 1](https://slidetodoc.com/presentation_image_h/01ead8ee490c87c1c79a032f1a2ae82c/image-1.jpg)
![Concepts • Electric generator • Magnetic flux • Induced EMF 2/19/2021 Lecture VIII 2 Concepts • Electric generator • Magnetic flux • Induced EMF 2/19/2021 Lecture VIII 2](https://slidetodoc.com/presentation_image_h/01ead8ee490c87c1c79a032f1a2ae82c/image-2.jpg)
![Electric motor electric generator • Electric motor: – electric energy mechanical. • Electric generator: Electric motor electric generator • Electric motor: – electric energy mechanical. • Electric generator:](https://slidetodoc.com/presentation_image_h/01ead8ee490c87c1c79a032f1a2ae82c/image-3.jpg)
![Magnetic flux • If magnetic field is rain – magnetic flux is the amount Magnetic flux • If magnetic field is rain – magnetic flux is the amount](https://slidetodoc.com/presentation_image_h/01ead8ee490c87c1c79a032f1a2ae82c/image-4.jpg)
![Faraday’s Law of induction • Changing magnetic flux induces emf (voltage), • Acts like Faraday’s Law of induction • Changing magnetic flux induces emf (voltage), • Acts like](https://slidetodoc.com/presentation_image_h/01ead8ee490c87c1c79a032f1a2ae82c/image-5.jpg)
![Lenz’s Law: conservatism of nature • An induced emf always gives rise to a Lenz’s Law: conservatism of nature • An induced emf always gives rise to a](https://slidetodoc.com/presentation_image_h/01ead8ee490c87c1c79a032f1a2ae82c/image-6.jpg)
![Moving conductor • A conducting rod is moving to the right on a U-shaped Moving conductor • A conducting rod is moving to the right on a U-shaped](https://slidetodoc.com/presentation_image_h/01ead8ee490c87c1c79a032f1a2ae82c/image-7.jpg)
![Electric generator • Electric generator: – conductor loop rotating in magnetic field produces – Electric generator • Electric generator: – conductor loop rotating in magnetic field produces –](https://slidetodoc.com/presentation_image_h/01ead8ee490c87c1c79a032f1a2ae82c/image-8.jpg)
![Alternating current (AC) • Emf changes sign current changes the direction I Req ~ Alternating current (AC) • Emf changes sign current changes the direction I Req ~](https://slidetodoc.com/presentation_image_h/01ead8ee490c87c1c79a032f1a2ae82c/image-9.jpg)
![Transformer • If all flux goes through the core: 2/19/2021 Lecture VIII 10 Transformer • If all flux goes through the core: 2/19/2021 Lecture VIII 10](https://slidetodoc.com/presentation_image_h/01ead8ee490c87c1c79a032f1a2ae82c/image-10.jpg)
![Transformer • If energy is conserved • If efficiency e<100% 2/19/2021 Lecture VIII 11 Transformer • If energy is conserved • If efficiency e<100% 2/19/2021 Lecture VIII 11](https://slidetodoc.com/presentation_image_h/01ead8ee490c87c1c79a032f1a2ae82c/image-11.jpg)
![Power transmission • High voltage low current power loss in power line resistance is Power transmission • High voltage low current power loss in power line resistance is](https://slidetodoc.com/presentation_image_h/01ead8ee490c87c1c79a032f1a2ae82c/image-12.jpg)
![Power transmission • 65 k. W is transmitted over two 0. 100 Ohm lines. Power transmission • 65 k. W is transmitted over two 0. 100 Ohm lines.](https://slidetodoc.com/presentation_image_h/01ead8ee490c87c1c79a032f1a2ae82c/image-13.jpg)
![Moving conductor – eddy currents • A increases F increases Induced current creates Bint Moving conductor – eddy currents • A increases F increases Induced current creates Bint](https://slidetodoc.com/presentation_image_h/01ead8ee490c87c1c79a032f1a2ae82c/image-14.jpg)
![Electric generator –counter torque • Loop is rotating cw • Induced currents experience force Electric generator –counter torque • Loop is rotating cw • Induced currents experience force](https://slidetodoc.com/presentation_image_h/01ead8ee490c87c1c79a032f1a2ae82c/image-15.jpg)
![Electric motor – counter emf • Current loop in magnetic field • Magnetic field Electric motor – counter emf • Current loop in magnetic field • Magnetic field](https://slidetodoc.com/presentation_image_h/01ead8ee490c87c1c79a032f1a2ae82c/image-16.jpg)
- Slides: 16
![Induced EMF Generators Transformers Physics 114 2192021 Lecture VIII 1 Induced EMF Generators , Transformers Physics 114 2/19/2021 Lecture VIII 1](https://slidetodoc.com/presentation_image_h/01ead8ee490c87c1c79a032f1a2ae82c/image-1.jpg)
Induced EMF Generators , Transformers Physics 114 2/19/2021 Lecture VIII 1
![Concepts Electric generator Magnetic flux Induced EMF 2192021 Lecture VIII 2 Concepts • Electric generator • Magnetic flux • Induced EMF 2/19/2021 Lecture VIII 2](https://slidetodoc.com/presentation_image_h/01ead8ee490c87c1c79a032f1a2ae82c/image-2.jpg)
Concepts • Electric generator • Magnetic flux • Induced EMF 2/19/2021 Lecture VIII 2
![Electric motor electric generator Electric motor electric energy mechanical Electric generator Electric motor electric generator • Electric motor: – electric energy mechanical. • Electric generator:](https://slidetodoc.com/presentation_image_h/01ead8ee490c87c1c79a032f1a2ae82c/image-3.jpg)
Electric motor electric generator • Electric motor: – electric energy mechanical. • Electric generator: – Current loop rotates in – mechanical electric energy magnetic field – conductor loop rotating in magnetic field produces electric current 2/19/2021 Lecture VIII 3
![Magnetic flux If magnetic field is rain magnetic flux is the amount Magnetic flux • If magnetic field is rain – magnetic flux is the amount](https://slidetodoc.com/presentation_image_h/01ead8ee490c87c1c79a032f1a2ae82c/image-4.jpg)
Magnetic flux • If magnetic field is rain – magnetic flux is the amount of water in a bucket accumulated per unit of time: • Magnetic flux is measured in Weber: 1 Wb=1 T. m 2 2/19/2021 Lecture VIII Three ways to change flux • Change B • Change A • Change q 4
![Faradays Law of induction Changing magnetic flux induces emf voltage Acts like Faraday’s Law of induction • Changing magnetic flux induces emf (voltage), • Acts like](https://slidetodoc.com/presentation_image_h/01ead8ee490c87c1c79a032f1a2ae82c/image-5.jpg)
Faraday’s Law of induction • Changing magnetic flux induces emf (voltage), • Acts like a battery! 2/19/2021 Lecture VIII 5
![Lenzs Law conservatism of nature An induced emf always gives rise to a Lenz’s Law: conservatism of nature • An induced emf always gives rise to a](https://slidetodoc.com/presentation_image_h/01ead8ee490c87c1c79a032f1a2ae82c/image-6.jpg)
Lenz’s Law: conservatism of nature • An induced emf always gives rise to a current whose magnetic field opposes the original change in flux: – Flux decreases internal Bint (created by the induced current) is in the same direction as the external Bext – Flux increases Bint – in the opposite direction to Bext – Determine current direction using 1 st right hand rule 2/19/2021 Lecture VIII 6
![Moving conductor A conducting rod is moving to the right on a Ushaped Moving conductor • A conducting rod is moving to the right on a U-shaped](https://slidetodoc.com/presentation_image_h/01ead8ee490c87c1c79a032f1a2ae82c/image-7.jpg)
Moving conductor • A conducting rod is moving to the right on a U-shaped conductor in a uniform magnetic field flux is increasing • Induced emf: 2/19/2021 • Induced electric field: Lecture VIII 7
![Electric generator Electric generator conductor loop rotating in magnetic field produces Electric generator • Electric generator: – conductor loop rotating in magnetic field produces –](https://slidetodoc.com/presentation_image_h/01ead8ee490c87c1c79a032f1a2ae82c/image-8.jpg)
Electric generator • Electric generator: – conductor loop rotating in magnetic field produces – Alternating electric current AC 2/19/2021 Lecture VIII 8
![Alternating current AC Emf changes sign current changes the direction I Req Alternating current (AC) • Emf changes sign current changes the direction I Req ~](https://slidetodoc.com/presentation_image_h/01ead8ee490c87c1c79a032f1a2ae82c/image-9.jpg)
Alternating current (AC) • Emf changes sign current changes the direction I Req ~ 2/19/2021 Lecture VIII 9
![Transformer If all flux goes through the core 2192021 Lecture VIII 10 Transformer • If all flux goes through the core: 2/19/2021 Lecture VIII 10](https://slidetodoc.com/presentation_image_h/01ead8ee490c87c1c79a032f1a2ae82c/image-10.jpg)
Transformer • If all flux goes through the core: 2/19/2021 Lecture VIII 10
![Transformer If energy is conserved If efficiency e100 2192021 Lecture VIII 11 Transformer • If energy is conserved • If efficiency e<100% 2/19/2021 Lecture VIII 11](https://slidetodoc.com/presentation_image_h/01ead8ee490c87c1c79a032f1a2ae82c/image-11.jpg)
Transformer • If energy is conserved • If efficiency e<100% 2/19/2021 Lecture VIII 11
![Power transmission High voltage low current power loss in power line resistance is Power transmission • High voltage low current power loss in power line resistance is](https://slidetodoc.com/presentation_image_h/01ead8ee490c87c1c79a032f1a2ae82c/image-12.jpg)
Power transmission • High voltage low current power loss in power line resistance is lower: Power is dissipated only in resistors!!! 2/19/2021 Lecture VIII 12
![Power transmission 65 k W is transmitted over two 0 100 Ohm lines Power transmission • 65 k. W is transmitted over two 0. 100 Ohm lines.](https://slidetodoc.com/presentation_image_h/01ead8ee490c87c1c79a032f1a2ae82c/image-13.jpg)
Power transmission • 65 k. W is transmitted over two 0. 100 Ohm lines. • V=120 1200 V 120 V, e=99% • Compare losses to power transmission at 120 V 2/19/2021 Lecture VIII 13
![Moving conductor eddy currents A increases F increases Induced current creates Bint Moving conductor – eddy currents • A increases F increases Induced current creates Bint](https://slidetodoc.com/presentation_image_h/01ead8ee490c87c1c79a032f1a2ae82c/image-14.jpg)
Moving conductor – eddy currents • A increases F increases Induced current creates Bint opposite to external Bext • I down • Now we have a current in magnetic field there is a force acting on it • The direction of this force is opposite to v • Conservatism of nature • Currents created in conductors moving through the magnetic field – eddy currents – work to resist the change 2/19/2021 Lecture VIII 14
![Electric generator counter torque Loop is rotating cw Induced currents experience force Electric generator –counter torque • Loop is rotating cw • Induced currents experience force](https://slidetodoc.com/presentation_image_h/01ead8ee490c87c1c79a032f1a2ae82c/image-15.jpg)
Electric generator –counter torque • Loop is rotating cw • Induced currents experience force in magnetic field resultant torque on the loop ccw – counter torque • Nature resists change. 2/19/2021 Lecture VIII 15
![Electric motor counter emf Current loop in magnetic field Magnetic field Electric motor – counter emf • Current loop in magnetic field • Magnetic field](https://slidetodoc.com/presentation_image_h/01ead8ee490c87c1c79a032f1a2ae82c/image-16.jpg)
Electric motor – counter emf • Current loop in magnetic field • Magnetic field creates a torque that rotates the loop • Changing flux emf • Based on conservatism – this emf will try to create a current in the opposite direction to the original current - counter emf. • Current is large at the beginning and is decreased later on. 2/19/2021 Lecture VIII 16
( 0 0 299 587 114 ) | ( 0 0 299 587 )
State the ideal transformer equation
Faraday's law
Emf induced in a moving conductor
Faraday's law of induction
Emf induced in a moving conductor
Induced dipole induced dipole interaction
Transformers physics
Generator
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Rts transformer
Caminar las estaciones
Sas 114 letter sample
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