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brightspark
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just google it like everybody else does then u can be an expert tooShe's on a engineering course and has to come up with an answer for the following question but she's a bit overwhelmed
Please use small words so i know what your talking about
Can anyone explain what magnetic permittivity and one practical application of it?
just google it like everybody else does then u can be an expert too
Remember the bit about small words
Google made my brain hurt
brightspark
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Remember the bit about small words
u mean u want it in laymans language not long winded bull\\\****
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rtbcomp
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Does she mean permeability? This seems to apply to magnets, whereas permittivity seems to apply to capacitors.
http://www.mcasco.com/Answers/qa_mop.html
http://www.mcasco.com/Answers/qa_mop.html
zardoz
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What i found Googling was:
Permitivity: A measure of the ability of a material to resist the formation of an electric field within it.
also found:
http://en.wikipedia.org/wiki/Magnetic_permittivity
Permitivity: A measure of the ability of a material to resist the formation of an electric field within it.
also found:
http://en.wikipedia.org/wiki/Magnetic_permittivity
I have never heard of the term "magnetic permittivity". There is electric permittivity, which is the property of a material that determines the propagation of an electric field. The equivalent for a magnetic field is called "permeability", as mentioned above.
Can't she do a search on the Internet?
Can't she do a search on the Internet?
If your friend is doing a btec mech eng, she probably has to do a electrical engineering unit as part of it, and the subject covers magnetic permeability as rtbcomp has suggested already. I have memories of that unit many years ago going into the depth of deriving mu using the constant 4pi x 10-7 in webers/m2 or something from first principles as part of it (im probably wrong, im going off memory and it was 23 years back!) , then it goes onto its application in motors and generators and flemmings rules and lots of students pointing their fingers looking puzzled in lectures etc. And I have used that entire module since learning it well exactly 0 times since
:-
http://en.wikipedia.org/wiki/Permeability_(electromagnetism)
If your friend is doing a btec mech eng, she probably has to do a electrical engineering unit as part of it, and the subject covers magnetic permeability as rtbcomp has suggested already. I have memories of that unit many years ago going into the depth of deriving mu using the constant 4pi x 10-7 in webers/m2 or something from first principles as part of it (im probably wrong, im going off memory and it was 23 years back!) , then it goes onto its application in motors and generators and flemmings rules and lots of students pointing their fingers looking puzzled in lectures etc. And I have used that entire module since learning it well exactly 0 times since
:-
http://en.wikipedia.org/wiki/Permeability_(electromagnetism)
I did ask my boss how knowing how electrons move in a metal would help me wire a plug! I don't mind though, it's interesting if not directly relevant
In laymans terms, its how magnetty a substance is. And webers is a unit for measure of magnetism.
Ask your friend if they still do the cat friction joke also (two cats sliding down a tin roof, which one falls off first? the one with the lowest Mu.... Mu is the co-efficient of friction, you have to say it out loud... its still crap though... )
Ask your friend if they still do the cat friction joke also (two cats sliding down a tin roof, which one falls off first? the one with the lowest Mu.... Mu is the co-efficient of friction, you have to say it out loud... its still crap though... )
puffernutter
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It would appear it means how easily you can polarise a piece of metal with a magnetic field. An example I would give is a solenoid (or relay) where the permittivity is such that when a coil of wire is energised with a current and co-axial to that core is a steel rod, when the magnetic field is created by the current, the steel core moves (you can use a relay as just a good example).
It is also important in this application that when the current is removed from the coil, the magnetic field collapses and the steel core also loses its magnetism and returns to its original position (usually with the aid of a spring)
Does that help?
Cheers
Peter
It is also important in this application that when the current is removed from the coil, the magnetic field collapses and the steel core also loses its magnetism and returns to its original position (usually with the aid of a spring)
Does that help?
Cheers
Peter
Its a measure of how easily a space or material will allow magnetic flux to pass, not just limited to metal, plastic has a value of it, wood too, but much lower than ferrous materials.
Its probably best to refer to some text on the matter, sussex uni is probably a more reliable source than my memories from years ago, since I seem to have confused it with the units of intrinsic fields, doh. :-
http://info.ee.surrey.ac.uk/Workshop/advice/coils/mu/#mu
Its probably best to refer to some text on the matter, sussex uni is probably a more reliable source than my memories from years ago, since I seem to have confused it with the units of intrinsic fields, doh. :-
http://info.ee.surrey.ac.uk/Workshop/advice/coils/mu/#mu
If you want an example on the importance of considering permittivity:
Transformers - you have 1 electrical coil connected to a power source which converts the electricity to magnetic flux, a second coil then converts the magnetic flux to an electrical energy again, the ratio of turns in the input coil and output could will determine the voltage difference. If you add an iron core (High Permittivity) it improves the generation of the magnetic filed and hence the efficiency of the transformer.
Transformers - you have 1 electrical coil connected to a power source which converts the electricity to magnetic flux, a second coil then converts the magnetic flux to an electrical energy again, the ratio of turns in the input coil and output could will determine the voltage difference. If you add an iron core (High Permittivity) it improves the generation of the magnetic filed and hence the efficiency of the transformer.
