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how do eddy currents work? (1 Viewer)
- Thread starter coroneos
- Start date
Someone correct me:
When there is relative motion between an external magnetic field and a metallic object, an eddy current is induced in the object.
Because we are moving a current thorgh this magnetic field, the current sets up its own magnetic field to try and oppose this motion, creating some resistance
eddy currents are circular currents that are the basis of electro-braking etc
i may be wrong, but either way, i'll learn
-Rev
When there is relative motion between an external magnetic field and a metallic object, an eddy current is induced in the object.
Because we are moving a current thorgh this magnetic field, the current sets up its own magnetic field to try and oppose this motion, creating some resistance
eddy currents are circular currents that are the basis of electro-braking etc
i may be wrong, but either way, i'll learn
-Rev
Rahul
Dead Member
you may also want to include lenz's law in it too.
having the correct terminology helps.
having the correct terminology helps.
Rahul
Dead Member
no problems
also you may want to look at the heating effects of eddy currents in its applications and the problems it creates and how they are solved.
application: induction cooktops.
problems: the build up heat can damage the parts and is essentialy a waste of energy.
solutions: instead of a 'chunk' of metal, there are sheets of metals that are covered by laminate. this stops the current from building up.
also you may want to look at the heating effects of eddy currents in its applications and the problems it creates and how they are solved.
application: induction cooktops.
problems: the build up heat can damage the parts and is essentialy a waste of energy.
solutions: instead of a 'chunk' of metal, there are sheets of metals that are covered by laminate. this stops the current from building up.
N
ND
Guest
A current will always have a magnetic field. It doesn't create a magnetic field because it's in one.
Rahul
Dead Member
yeh, ur right ND
Because we are moving a current thorgh this magnetic field, the current sets up its own magnetic field.
this should have been written: Because we are moving a conductor through this magnetic field, a current is induced, the current sets up its own magnetic field.
i think thats what rev meant...
Because we are moving a current thorgh this magnetic field, the current sets up its own magnetic field.
this should have been written: Because we are moving a conductor through this magnetic field, a current is induced, the current sets up its own magnetic field.
i think thats what rev meant...
Rahul
Dead Member
ND was only tryin to help...Originally posted by dandaman
sorry einstein, im sure they didnt make that mistake delibrately
N
ND
Guest
Umm he asked for help ("i may be wrong, but either way, i'll learnOriginally posted by dandaman
sorry einstein, im sure they didnt make that mistake delibrately
"). It's better he learns now, before the exam. If i've got something wrong, i'd sure appreciate somebody telling me.
coroneos
Member
- Joined
- Sep 5, 2003
- Messages
- 679
Eddy Currents
When a solid conductor is placed in a region of changing magnetic flux, circular eddy currents are induced in the conductor. Lenzs Law can be used to explain the direction of flow of eddy currents in particular cases. Consider the case below. A uniform magnetic field is set up by placing a magnetic north pole above the plane of this page and a south pole below the plane of the page. The magnetic field direction is therefore down into the page as shown. Next a copper sheet originally sitting stationary in the magnetic field is pulled out of the field in the plane of the page as shown below. By Faradays Law, eddy currents will form where there is a change of flux with time, that is along the right hand edge of the field where the metal sheet is leaving the field.
That was taken from http://webs.mn.catholic.edu.au
When a solid conductor is placed in a region of changing magnetic flux, circular eddy currents are induced in the conductor. Lenzs Law can be used to explain the direction of flow of eddy currents in particular cases. Consider the case below. A uniform magnetic field is set up by placing a magnetic north pole above the plane of this page and a south pole below the plane of the page. The magnetic field direction is therefore down into the page as shown. Next a copper sheet originally sitting stationary in the magnetic field is pulled out of the field in the plane of the page as shown below. By Faradays Law, eddy currents will form where there is a change of flux with time, that is along the right hand edge of the field where the metal sheet is leaving the field.
That was taken from http://webs.mn.catholic.edu.au
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