Nov 10, 2014

Energy Stored in Magnetic Field



energy-stored-in-magnetic-field

We know that energy is needed to ascertain flux i.e. magnetic flux however it's not needed to keep up it. This is often kind of like the actual fact that the energy is needed to lift the water through an exact height (h) that is 'mgh' joules. However energy isn't needed to keep up the water at height 'h'. This energy 'mgh' gets hold on in it as its potential energy and may be used for several functions.

Explanation

Consider a solenoid, current through which may be controlled with the assistance of switch S, resistance R shown within the above fig.

Initially switch ‘S' is open, thus current through coil, I is zero. Once switch is closed, current can attempt to build its value capable to I. Neglect the resistance of coil.

It will take time to extend this from 'zero' to 'l' say 'dt’ seconds. within the in the meantime, flux linkages related to the coil can change, because of that there'll be self-induced e.m.f. within the coil whose value is given by,
                                e = -L (dI/dt)

So at each instant, coil can attempt to oppose the rise within the current. To beat this opposition, supply must give the energy to the circuit. This is often nothing however the energy needed to ascertain this i.e. magnetic flux or flux round the coil.

The minute current reaches its most value '' then change in current stops. Thus there can't be any induced e.m.f. within the coil and no energy is going to be drawn from the source. Thus no energy is needed to keep up the established flux. This is often because; induced e.m.f. lasts as long as there's alteration in flux lines related to the coil, in line with Faraday's law.

When current is once more reduced to zero by opening the switch then current through the coil starts reducing and flux starts reducing. Thus there's induced e.m.f. within the coil in line with Faraday's law. However as per Lenz's law it'll attempt to oppose because creating it that is decrease in current. Thus this induced e.m.f. currently can attempt to maintain current to its original value. So instantly this induced e.m.f. acts as a supply and provides the energy to the supply. This is often nothing however identical energy that is hold on within the magnetic flux that gets recovered whereas field collapses. Thus energy holds on whereas increase within the current is reverted back to the source once current decreases i.e. once field collapses.







13 Comments
Comments

Read Comment Policy
We have Zero Tolerance to Spam. Chessy Comments and Comments with Links will be deleted immediately upon our review.

  1. Hi, Really great effort. Everyone must read this article. Thanks for sharing.

    ReplyDelete
  2. Hi, Really great effort. Everyone must read this article. Thanks for sharing.

    ReplyDelete
  3. Hi, Really great effort. Everyone must read this article. Thanks for sharing.

    ReplyDelete
  4. Amazing blog and very interesting stuff you got here! I definitely learned a lot from reading through some of your earlier posts as well and decided to drop a comment on this one!

    ReplyDelete
  5. Amazing blog and very interesting stuff you got here! I definitely learned a lot from reading through some of your earlier posts as well and decided to drop a comment on this one!

    ReplyDelete
  6. Very informative post for me as I am always looking for new content that can help me and my knowledge grow better.

    ReplyDelete
  7. Very informative post for me as I am always looking for new content that can help me and my knowledge grow better.

    ReplyDelete
  8. Look at run-time @ 1000W burden, highlights and more with my audits. ... Champion 7500W Double Fuel - My #1 Decision for Best Double Fuel Generator ... inverter generator 3000 watt

    ReplyDelete
  9. Thanks for the post and great tips..even I also think that hard work is the most important aspect of getting success Zonnepanelen

    ReplyDelete
  10. Solar power is a "green" and sustainable power and doesn't radiate hurtful carbon dioxide, which implies it's an incredible method to lessen your carbon impression. Zonnepanelen

    ReplyDelete
  11. This is significant since carbon discharges are hazardous and maintaining a strategic distance from their outflow helps in protecting our present and future condition. Zonnepanelen

    ReplyDelete
  12. Lamentably, the rising vitality costs are digging in for the long haul.Zonnepanelen

    ReplyDelete
  13. Very nice article, I enjoyed reading your post, very nice share, I want to twit this to my followers. Thanks!. bring me the news

    ReplyDelete