Permanent Magnetic Field vs Electromagnetic Field












6














If I put a permanent magnet under a box and an energized electromagnetic coil under another box could you tell me which box was covering the permanent magnet? If the answer is yes what test would you use?
Note: The coil is receiving a steady dc current.






electromagnetism magnetic-fields







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  • Is the supply current assumed to be essentially unlimited? Because if not, it will eventually deplete.
    – Alex S
    yesterday










  • @AlexS Yes, a continuous supply.
    – Lambda
    yesterday
















6














If I put a permanent magnet under a box and an energized electromagnetic coil under another box could you tell me which box was covering the permanent magnet? If the answer is yes what test would you use?
Note: The coil is receiving a steady dc current.






electromagnetism magnetic-fields







share|cite|improve this question






















  • Is the supply current assumed to be essentially unlimited? Because if not, it will eventually deplete.
    – Alex S
    yesterday










  • @AlexS Yes, a continuous supply.
    – Lambda
    yesterday














6












6








6







If I put a permanent magnet under a box and an energized electromagnetic coil under another box could you tell me which box was covering the permanent magnet? If the answer is yes what test would you use?
Note: The coil is receiving a steady dc current.






electromagnetism magnetic-fields







share|cite|improve this question













If I put a permanent magnet under a box and an energized electromagnetic coil under another box could you tell me which box was covering the permanent magnet? If the answer is yes what test would you use?
Note: The coil is receiving a steady dc current.






electromagnetism magnetic-fields




electromagnetism magnetic-fields






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asked 2 days ago









LambdaLambda

2,51641126




2,51641126












  • Is the supply current assumed to be essentially unlimited? Because if not, it will eventually deplete.
    – Alex S
    yesterday










  • @AlexS Yes, a continuous supply.
    – Lambda
    yesterday


















  • Is the supply current assumed to be essentially unlimited? Because if not, it will eventually deplete.
    – Alex S
    yesterday










  • @AlexS Yes, a continuous supply.
    – Lambda
    yesterday
















Is the supply current assumed to be essentially unlimited? Because if not, it will eventually deplete.
– Alex S
yesterday




Is the supply current assumed to be essentially unlimited? Because if not, it will eventually deplete.
– Alex S
yesterday












@AlexS Yes, a continuous supply.
– Lambda
yesterday




@AlexS Yes, a continuous supply.
– Lambda
yesterday










6 Answers
6






active

oldest

votes


















16














The box containing the coil will heat up more and more due to the joule effect. So measuring the temperature you could tell.






share|cite|improve this answer





























    8














    If this is a normal coil wound with resistance wire, then around the coil with current will be the electric field and magnetic field, and around the permanent magnet only magnetic field. If the boxes do not shield the electric field, it will not be difficult to detect the coil with current by measuring the electric field.






    share|cite|improve this answer





















    • there are "non contact voltage testers" on the market.amazon.com/Voltage-Detector-Non-Contact-Electric-12~220V/dp/… . Here is a report on DC testers e-reports-ext.llnl.gov/pdf/374701.pdf
      – anna v
      2 days ago










    • @annav Thank you, I have it.
      – Alex Trounev
      2 days ago










    • @annav Thanks for posting the links. I am wondering if the probes wouldn’t also measure the magnetic field.
      – Lambda
      2 days ago










    • @Lambda if you look at the designs ,no. they are designed for electrif fields
      – anna v
      2 days ago



















    7














    Warm it up near or beyond the Curie temperature, it will make no difference to the coil but the "permanent" becomes "impermanent".






    share|cite|improve this answer





























      4














      If the permanent magnet and the electromagnet are shaped so that the field in the box has precisely the same shape, there is no way to know which box covers which magnet, simply by measuring the field using a tiny probe magnet or tiny probe coil with very small current.



      However, it may be possible to distinguish between the two cases by a more "intrusive" measurement: A metal detector, for example, would very likely respond slightly differently for one than the other. The electromagnet coil would act as a transformer secondary if driven by an electromagnet above the box, and should behave in a slightly different way than the permanent magnet.



      Edited for clarity: "Driven" means, in this context, that the electromagnet above the box is energized by a time-varying current, which will produce a time-varying field, which in turn will "drive" a time-varying additional EMF in the coil below the box.






      share|cite|improve this answer



















      • 1




        Transformers do not work for DC.
        – my2cts
        2 days ago










      • I guess "driven" needs to be clarified.
        – S. McGrew
        2 days ago



















      2














      With an x-ray snapshot you should be able to see the difference :). However the magnetic fields can be made to be indistinguishable within certain intensity limits. There is a limit to what a permanent magnet can achieve in a certain volume. An electromagnet can produce a much stronger field.



      See https://hypertextbook.com/facts/2000/AnnaWoo.shtml .






      share|cite|improve this answer























      • Are you saying that the information in th elink is wrong? It states that the strongest permanent field is 0.1 T, much less that that of a steady state electromagnet. Do you have a reference for your statement?
        – my2cts
        2 days ago






      • 1




        @Sparky256 Btw: some electromagnets can exceed 10T. Obviously continuously, as they are superconducting. Here is a link: home.cern/news/news/engineering/…
        – cmaster
        2 days ago










      • @Sparky256 You claim my answer is wrong. Do you have a reference to show for it ?
        – my2cts
        yesterday



















      0














      Electromagnets can produce a stronger pulsed field, but not a steady-state field as the windings would burn up fast. Oddly enough the same intense magnetic pulse is used to magnetize neodymium-iron-born (NIB) magnets.



      For a steady-state magnetic field (not superconducting) NIB alloys have the strongest field for now. Some NIB alloys will tolerate intense heat at the cost of total field strength.






      share|cite|improve this answer



















      • 1




        This heavily depends on the coil material, and, perchance, the cooling. Superconducting magnets don't have any issue delivering extremely strong magnetic fields continuously, and they obviously classify as electromagnets...
        – cmaster
        2 days ago










      • @cmaster. I am aware of superconducting magnets, which can also transfer DC power as a superconducting transformer. Superconducting was not part of the OP's question, so it is not part of any answers. It would have to be posted as a separate question.
        – user219230
        2 days ago










      • The record for the strongest steady state field is 45T ( en.wikipedia.org/wiki/Orders_of_magnitude_(magnetic_field) ). I don't believe that permanent magnets reach fields anywhere near this value. Please show me the paper.
        – my2cts
        yesterday












      • @Sparky256 NIB magnets reach about 1T ( en.wikipedia.org/wiki/Neodymium_magnet#Magnetic_properties ).
        – my2cts
        yesterday











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      6 Answers
      6






      active

      oldest

      votes








      6 Answers
      6






      active

      oldest

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      active

      oldest

      votes






      active

      oldest

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      16














      The box containing the coil will heat up more and more due to the joule effect. So measuring the temperature you could tell.






      share|cite|improve this answer


























        16














        The box containing the coil will heat up more and more due to the joule effect. So measuring the temperature you could tell.






        share|cite|improve this answer
























          16












          16








          16






          The box containing the coil will heat up more and more due to the joule effect. So measuring the temperature you could tell.






          share|cite|improve this answer












          The box containing the coil will heat up more and more due to the joule effect. So measuring the temperature you could tell.







          share|cite|improve this answer












          share|cite|improve this answer



          share|cite|improve this answer










          answered 2 days ago









          Run like hellRun like hell

          1,318725




          1,318725























              8














              If this is a normal coil wound with resistance wire, then around the coil with current will be the electric field and magnetic field, and around the permanent magnet only magnetic field. If the boxes do not shield the electric field, it will not be difficult to detect the coil with current by measuring the electric field.






              share|cite|improve this answer





















              • there are "non contact voltage testers" on the market.amazon.com/Voltage-Detector-Non-Contact-Electric-12~220V/dp/… . Here is a report on DC testers e-reports-ext.llnl.gov/pdf/374701.pdf
                – anna v
                2 days ago










              • @annav Thank you, I have it.
                – Alex Trounev
                2 days ago










              • @annav Thanks for posting the links. I am wondering if the probes wouldn’t also measure the magnetic field.
                – Lambda
                2 days ago










              • @Lambda if you look at the designs ,no. they are designed for electrif fields
                – anna v
                2 days ago
















              8














              If this is a normal coil wound with resistance wire, then around the coil with current will be the electric field and magnetic field, and around the permanent magnet only magnetic field. If the boxes do not shield the electric field, it will not be difficult to detect the coil with current by measuring the electric field.






              share|cite|improve this answer





















              • there are "non contact voltage testers" on the market.amazon.com/Voltage-Detector-Non-Contact-Electric-12~220V/dp/… . Here is a report on DC testers e-reports-ext.llnl.gov/pdf/374701.pdf
                – anna v
                2 days ago










              • @annav Thank you, I have it.
                – Alex Trounev
                2 days ago










              • @annav Thanks for posting the links. I am wondering if the probes wouldn’t also measure the magnetic field.
                – Lambda
                2 days ago










              • @Lambda if you look at the designs ,no. they are designed for electrif fields
                – anna v
                2 days ago














              8












              8








              8






              If this is a normal coil wound with resistance wire, then around the coil with current will be the electric field and magnetic field, and around the permanent magnet only magnetic field. If the boxes do not shield the electric field, it will not be difficult to detect the coil with current by measuring the electric field.






              share|cite|improve this answer












              If this is a normal coil wound with resistance wire, then around the coil with current will be the electric field and magnetic field, and around the permanent magnet only magnetic field. If the boxes do not shield the electric field, it will not be difficult to detect the coil with current by measuring the electric field.







              share|cite|improve this answer












              share|cite|improve this answer



              share|cite|improve this answer










              answered 2 days ago









              Alex TrounevAlex Trounev

              31215




              31215












              • there are "non contact voltage testers" on the market.amazon.com/Voltage-Detector-Non-Contact-Electric-12~220V/dp/… . Here is a report on DC testers e-reports-ext.llnl.gov/pdf/374701.pdf
                – anna v
                2 days ago










              • @annav Thank you, I have it.
                – Alex Trounev
                2 days ago










              • @annav Thanks for posting the links. I am wondering if the probes wouldn’t also measure the magnetic field.
                – Lambda
                2 days ago










              • @Lambda if you look at the designs ,no. they are designed for electrif fields
                – anna v
                2 days ago


















              • there are "non contact voltage testers" on the market.amazon.com/Voltage-Detector-Non-Contact-Electric-12~220V/dp/… . Here is a report on DC testers e-reports-ext.llnl.gov/pdf/374701.pdf
                – anna v
                2 days ago










              • @annav Thank you, I have it.
                – Alex Trounev
                2 days ago










              • @annav Thanks for posting the links. I am wondering if the probes wouldn’t also measure the magnetic field.
                – Lambda
                2 days ago










              • @Lambda if you look at the designs ,no. they are designed for electrif fields
                – anna v
                2 days ago
















              there are "non contact voltage testers" on the market.amazon.com/Voltage-Detector-Non-Contact-Electric-12~220V/dp/… . Here is a report on DC testers e-reports-ext.llnl.gov/pdf/374701.pdf
              – anna v
              2 days ago




              there are "non contact voltage testers" on the market.amazon.com/Voltage-Detector-Non-Contact-Electric-12~220V/dp/… . Here is a report on DC testers e-reports-ext.llnl.gov/pdf/374701.pdf
              – anna v
              2 days ago












              @annav Thank you, I have it.
              – Alex Trounev
              2 days ago




              @annav Thank you, I have it.
              – Alex Trounev
              2 days ago












              @annav Thanks for posting the links. I am wondering if the probes wouldn’t also measure the magnetic field.
              – Lambda
              2 days ago




              @annav Thanks for posting the links. I am wondering if the probes wouldn’t also measure the magnetic field.
              – Lambda
              2 days ago












              @Lambda if you look at the designs ,no. they are designed for electrif fields
              – anna v
              2 days ago




              @Lambda if you look at the designs ,no. they are designed for electrif fields
              – anna v
              2 days ago











              7














              Warm it up near or beyond the Curie temperature, it will make no difference to the coil but the "permanent" becomes "impermanent".






              share|cite|improve this answer


























                7














                Warm it up near or beyond the Curie temperature, it will make no difference to the coil but the "permanent" becomes "impermanent".






                share|cite|improve this answer
























                  7












                  7








                  7






                  Warm it up near or beyond the Curie temperature, it will make no difference to the coil but the "permanent" becomes "impermanent".






                  share|cite|improve this answer












                  Warm it up near or beyond the Curie temperature, it will make no difference to the coil but the "permanent" becomes "impermanent".







                  share|cite|improve this answer












                  share|cite|improve this answer



                  share|cite|improve this answer










                  answered 2 days ago









                  hyportnexhyportnex

                  4,3271824




                  4,3271824























                      4














                      If the permanent magnet and the electromagnet are shaped so that the field in the box has precisely the same shape, there is no way to know which box covers which magnet, simply by measuring the field using a tiny probe magnet or tiny probe coil with very small current.



                      However, it may be possible to distinguish between the two cases by a more "intrusive" measurement: A metal detector, for example, would very likely respond slightly differently for one than the other. The electromagnet coil would act as a transformer secondary if driven by an electromagnet above the box, and should behave in a slightly different way than the permanent magnet.



                      Edited for clarity: "Driven" means, in this context, that the electromagnet above the box is energized by a time-varying current, which will produce a time-varying field, which in turn will "drive" a time-varying additional EMF in the coil below the box.






                      share|cite|improve this answer



















                      • 1




                        Transformers do not work for DC.
                        – my2cts
                        2 days ago










                      • I guess "driven" needs to be clarified.
                        – S. McGrew
                        2 days ago
















                      4














                      If the permanent magnet and the electromagnet are shaped so that the field in the box has precisely the same shape, there is no way to know which box covers which magnet, simply by measuring the field using a tiny probe magnet or tiny probe coil with very small current.



                      However, it may be possible to distinguish between the two cases by a more "intrusive" measurement: A metal detector, for example, would very likely respond slightly differently for one than the other. The electromagnet coil would act as a transformer secondary if driven by an electromagnet above the box, and should behave in a slightly different way than the permanent magnet.



                      Edited for clarity: "Driven" means, in this context, that the electromagnet above the box is energized by a time-varying current, which will produce a time-varying field, which in turn will "drive" a time-varying additional EMF in the coil below the box.






                      share|cite|improve this answer



















                      • 1




                        Transformers do not work for DC.
                        – my2cts
                        2 days ago










                      • I guess "driven" needs to be clarified.
                        – S. McGrew
                        2 days ago














                      4












                      4








                      4






                      If the permanent magnet and the electromagnet are shaped so that the field in the box has precisely the same shape, there is no way to know which box covers which magnet, simply by measuring the field using a tiny probe magnet or tiny probe coil with very small current.



                      However, it may be possible to distinguish between the two cases by a more "intrusive" measurement: A metal detector, for example, would very likely respond slightly differently for one than the other. The electromagnet coil would act as a transformer secondary if driven by an electromagnet above the box, and should behave in a slightly different way than the permanent magnet.



                      Edited for clarity: "Driven" means, in this context, that the electromagnet above the box is energized by a time-varying current, which will produce a time-varying field, which in turn will "drive" a time-varying additional EMF in the coil below the box.






                      share|cite|improve this answer














                      If the permanent magnet and the electromagnet are shaped so that the field in the box has precisely the same shape, there is no way to know which box covers which magnet, simply by measuring the field using a tiny probe magnet or tiny probe coil with very small current.



                      However, it may be possible to distinguish between the two cases by a more "intrusive" measurement: A metal detector, for example, would very likely respond slightly differently for one than the other. The electromagnet coil would act as a transformer secondary if driven by an electromagnet above the box, and should behave in a slightly different way than the permanent magnet.



                      Edited for clarity: "Driven" means, in this context, that the electromagnet above the box is energized by a time-varying current, which will produce a time-varying field, which in turn will "drive" a time-varying additional EMF in the coil below the box.







                      share|cite|improve this answer














                      share|cite|improve this answer



                      share|cite|improve this answer








                      edited 2 days ago

























                      answered 2 days ago









                      S. McGrewS. McGrew

                      7,34221131




                      7,34221131








                      • 1




                        Transformers do not work for DC.
                        – my2cts
                        2 days ago










                      • I guess "driven" needs to be clarified.
                        – S. McGrew
                        2 days ago














                      • 1




                        Transformers do not work for DC.
                        – my2cts
                        2 days ago










                      • I guess "driven" needs to be clarified.
                        – S. McGrew
                        2 days ago








                      1




                      1




                      Transformers do not work for DC.
                      – my2cts
                      2 days ago




                      Transformers do not work for DC.
                      – my2cts
                      2 days ago












                      I guess "driven" needs to be clarified.
                      – S. McGrew
                      2 days ago




                      I guess "driven" needs to be clarified.
                      – S. McGrew
                      2 days ago











                      2














                      With an x-ray snapshot you should be able to see the difference :). However the magnetic fields can be made to be indistinguishable within certain intensity limits. There is a limit to what a permanent magnet can achieve in a certain volume. An electromagnet can produce a much stronger field.



                      See https://hypertextbook.com/facts/2000/AnnaWoo.shtml .






                      share|cite|improve this answer























                      • Are you saying that the information in th elink is wrong? It states that the strongest permanent field is 0.1 T, much less that that of a steady state electromagnet. Do you have a reference for your statement?
                        – my2cts
                        2 days ago






                      • 1




                        @Sparky256 Btw: some electromagnets can exceed 10T. Obviously continuously, as they are superconducting. Here is a link: home.cern/news/news/engineering/…
                        – cmaster
                        2 days ago










                      • @Sparky256 You claim my answer is wrong. Do you have a reference to show for it ?
                        – my2cts
                        yesterday
















                      2














                      With an x-ray snapshot you should be able to see the difference :). However the magnetic fields can be made to be indistinguishable within certain intensity limits. There is a limit to what a permanent magnet can achieve in a certain volume. An electromagnet can produce a much stronger field.



                      See https://hypertextbook.com/facts/2000/AnnaWoo.shtml .






                      share|cite|improve this answer























                      • Are you saying that the information in th elink is wrong? It states that the strongest permanent field is 0.1 T, much less that that of a steady state electromagnet. Do you have a reference for your statement?
                        – my2cts
                        2 days ago






                      • 1




                        @Sparky256 Btw: some electromagnets can exceed 10T. Obviously continuously, as they are superconducting. Here is a link: home.cern/news/news/engineering/…
                        – cmaster
                        2 days ago










                      • @Sparky256 You claim my answer is wrong. Do you have a reference to show for it ?
                        – my2cts
                        yesterday














                      2












                      2








                      2






                      With an x-ray snapshot you should be able to see the difference :). However the magnetic fields can be made to be indistinguishable within certain intensity limits. There is a limit to what a permanent magnet can achieve in a certain volume. An electromagnet can produce a much stronger field.



                      See https://hypertextbook.com/facts/2000/AnnaWoo.shtml .






                      share|cite|improve this answer














                      With an x-ray snapshot you should be able to see the difference :). However the magnetic fields can be made to be indistinguishable within certain intensity limits. There is a limit to what a permanent magnet can achieve in a certain volume. An electromagnet can produce a much stronger field.



                      See https://hypertextbook.com/facts/2000/AnnaWoo.shtml .







                      share|cite|improve this answer














                      share|cite|improve this answer



                      share|cite|improve this answer








                      edited 2 days ago

























                      answered 2 days ago









                      my2ctsmy2cts

                      4,7432618




                      4,7432618












                      • Are you saying that the information in th elink is wrong? It states that the strongest permanent field is 0.1 T, much less that that of a steady state electromagnet. Do you have a reference for your statement?
                        – my2cts
                        2 days ago






                      • 1




                        @Sparky256 Btw: some electromagnets can exceed 10T. Obviously continuously, as they are superconducting. Here is a link: home.cern/news/news/engineering/…
                        – cmaster
                        2 days ago










                      • @Sparky256 You claim my answer is wrong. Do you have a reference to show for it ?
                        – my2cts
                        yesterday


















                      • Are you saying that the information in th elink is wrong? It states that the strongest permanent field is 0.1 T, much less that that of a steady state electromagnet. Do you have a reference for your statement?
                        – my2cts
                        2 days ago






                      • 1




                        @Sparky256 Btw: some electromagnets can exceed 10T. Obviously continuously, as they are superconducting. Here is a link: home.cern/news/news/engineering/…
                        – cmaster
                        2 days ago










                      • @Sparky256 You claim my answer is wrong. Do you have a reference to show for it ?
                        – my2cts
                        yesterday
















                      Are you saying that the information in th elink is wrong? It states that the strongest permanent field is 0.1 T, much less that that of a steady state electromagnet. Do you have a reference for your statement?
                      – my2cts
                      2 days ago




                      Are you saying that the information in th elink is wrong? It states that the strongest permanent field is 0.1 T, much less that that of a steady state electromagnet. Do you have a reference for your statement?
                      – my2cts
                      2 days ago




                      1




                      1




                      @Sparky256 Btw: some electromagnets can exceed 10T. Obviously continuously, as they are superconducting. Here is a link: home.cern/news/news/engineering/…
                      – cmaster
                      2 days ago




                      @Sparky256 Btw: some electromagnets can exceed 10T. Obviously continuously, as they are superconducting. Here is a link: home.cern/news/news/engineering/…
                      – cmaster
                      2 days ago












                      @Sparky256 You claim my answer is wrong. Do you have a reference to show for it ?
                      – my2cts
                      yesterday




                      @Sparky256 You claim my answer is wrong. Do you have a reference to show for it ?
                      – my2cts
                      yesterday











                      0














                      Electromagnets can produce a stronger pulsed field, but not a steady-state field as the windings would burn up fast. Oddly enough the same intense magnetic pulse is used to magnetize neodymium-iron-born (NIB) magnets.



                      For a steady-state magnetic field (not superconducting) NIB alloys have the strongest field for now. Some NIB alloys will tolerate intense heat at the cost of total field strength.






                      share|cite|improve this answer



















                      • 1




                        This heavily depends on the coil material, and, perchance, the cooling. Superconducting magnets don't have any issue delivering extremely strong magnetic fields continuously, and they obviously classify as electromagnets...
                        – cmaster
                        2 days ago










                      • @cmaster. I am aware of superconducting magnets, which can also transfer DC power as a superconducting transformer. Superconducting was not part of the OP's question, so it is not part of any answers. It would have to be posted as a separate question.
                        – user219230
                        2 days ago










                      • The record for the strongest steady state field is 45T ( en.wikipedia.org/wiki/Orders_of_magnitude_(magnetic_field) ). I don't believe that permanent magnets reach fields anywhere near this value. Please show me the paper.
                        – my2cts
                        yesterday












                      • @Sparky256 NIB magnets reach about 1T ( en.wikipedia.org/wiki/Neodymium_magnet#Magnetic_properties ).
                        – my2cts
                        yesterday
















                      0














                      Electromagnets can produce a stronger pulsed field, but not a steady-state field as the windings would burn up fast. Oddly enough the same intense magnetic pulse is used to magnetize neodymium-iron-born (NIB) magnets.



                      For a steady-state magnetic field (not superconducting) NIB alloys have the strongest field for now. Some NIB alloys will tolerate intense heat at the cost of total field strength.






                      share|cite|improve this answer



















                      • 1




                        This heavily depends on the coil material, and, perchance, the cooling. Superconducting magnets don't have any issue delivering extremely strong magnetic fields continuously, and they obviously classify as electromagnets...
                        – cmaster
                        2 days ago










                      • @cmaster. I am aware of superconducting magnets, which can also transfer DC power as a superconducting transformer. Superconducting was not part of the OP's question, so it is not part of any answers. It would have to be posted as a separate question.
                        – user219230
                        2 days ago










                      • The record for the strongest steady state field is 45T ( en.wikipedia.org/wiki/Orders_of_magnitude_(magnetic_field) ). I don't believe that permanent magnets reach fields anywhere near this value. Please show me the paper.
                        – my2cts
                        yesterday












                      • @Sparky256 NIB magnets reach about 1T ( en.wikipedia.org/wiki/Neodymium_magnet#Magnetic_properties ).
                        – my2cts
                        yesterday














                      0












                      0








                      0






                      Electromagnets can produce a stronger pulsed field, but not a steady-state field as the windings would burn up fast. Oddly enough the same intense magnetic pulse is used to magnetize neodymium-iron-born (NIB) magnets.



                      For a steady-state magnetic field (not superconducting) NIB alloys have the strongest field for now. Some NIB alloys will tolerate intense heat at the cost of total field strength.






                      share|cite|improve this answer














                      Electromagnets can produce a stronger pulsed field, but not a steady-state field as the windings would burn up fast. Oddly enough the same intense magnetic pulse is used to magnetize neodymium-iron-born (NIB) magnets.



                      For a steady-state magnetic field (not superconducting) NIB alloys have the strongest field for now. Some NIB alloys will tolerate intense heat at the cost of total field strength.







                      share|cite|improve this answer














                      share|cite|improve this answer



                      share|cite|improve this answer








                      edited 2 days ago









                      Peter Mortensen

                      1,93011323




                      1,93011323










                      answered 2 days ago







                      user219230















                      • 1




                        This heavily depends on the coil material, and, perchance, the cooling. Superconducting magnets don't have any issue delivering extremely strong magnetic fields continuously, and they obviously classify as electromagnets...
                        – cmaster
                        2 days ago










                      • @cmaster. I am aware of superconducting magnets, which can also transfer DC power as a superconducting transformer. Superconducting was not part of the OP's question, so it is not part of any answers. It would have to be posted as a separate question.
                        – user219230
                        2 days ago










                      • The record for the strongest steady state field is 45T ( en.wikipedia.org/wiki/Orders_of_magnitude_(magnetic_field) ). I don't believe that permanent magnets reach fields anywhere near this value. Please show me the paper.
                        – my2cts
                        yesterday












                      • @Sparky256 NIB magnets reach about 1T ( en.wikipedia.org/wiki/Neodymium_magnet#Magnetic_properties ).
                        – my2cts
                        yesterday














                      • 1




                        This heavily depends on the coil material, and, perchance, the cooling. Superconducting magnets don't have any issue delivering extremely strong magnetic fields continuously, and they obviously classify as electromagnets...
                        – cmaster
                        2 days ago










                      • @cmaster. I am aware of superconducting magnets, which can also transfer DC power as a superconducting transformer. Superconducting was not part of the OP's question, so it is not part of any answers. It would have to be posted as a separate question.
                        – user219230
                        2 days ago










                      • The record for the strongest steady state field is 45T ( en.wikipedia.org/wiki/Orders_of_magnitude_(magnetic_field) ). I don't believe that permanent magnets reach fields anywhere near this value. Please show me the paper.
                        – my2cts
                        yesterday












                      • @Sparky256 NIB magnets reach about 1T ( en.wikipedia.org/wiki/Neodymium_magnet#Magnetic_properties ).
                        – my2cts
                        yesterday








                      1




                      1




                      This heavily depends on the coil material, and, perchance, the cooling. Superconducting magnets don't have any issue delivering extremely strong magnetic fields continuously, and they obviously classify as electromagnets...
                      – cmaster
                      2 days ago




                      This heavily depends on the coil material, and, perchance, the cooling. Superconducting magnets don't have any issue delivering extremely strong magnetic fields continuously, and they obviously classify as electromagnets...
                      – cmaster
                      2 days ago












                      @cmaster. I am aware of superconducting magnets, which can also transfer DC power as a superconducting transformer. Superconducting was not part of the OP's question, so it is not part of any answers. It would have to be posted as a separate question.
                      – user219230
                      2 days ago




                      @cmaster. I am aware of superconducting magnets, which can also transfer DC power as a superconducting transformer. Superconducting was not part of the OP's question, so it is not part of any answers. It would have to be posted as a separate question.
                      – user219230
                      2 days ago












                      The record for the strongest steady state field is 45T ( en.wikipedia.org/wiki/Orders_of_magnitude_(magnetic_field) ). I don't believe that permanent magnets reach fields anywhere near this value. Please show me the paper.
                      – my2cts
                      yesterday






                      The record for the strongest steady state field is 45T ( en.wikipedia.org/wiki/Orders_of_magnitude_(magnetic_field) ). I don't believe that permanent magnets reach fields anywhere near this value. Please show me the paper.
                      – my2cts
                      yesterday














                      @Sparky256 NIB magnets reach about 1T ( en.wikipedia.org/wiki/Neodymium_magnet#Magnetic_properties ).
                      – my2cts
                      yesterday




                      @Sparky256 NIB magnets reach about 1T ( en.wikipedia.org/wiki/Neodymium_magnet#Magnetic_properties ).
                      – my2cts
                      yesterday


















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