Inductor anyone?

A solenoid of self-inductance L, is allowed to reach steady state by connecting to a battery of emf E and internal resistance R.

Now, a soft iron core is quickly inserted in the solenoid such that the coefficient of self inductance changes from L to nL.

Determine the current in the circuit at the time of complete insertion.

11 comments:

  1. And I thought if people mark something "too easy".. they already have the answer!

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  2. i thought that answer is e/r (just after the coil is inserted quickly) and same e/r (when the steady state is reached)

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  3. oh my god
    its too simple
    faltu mein itni complications kar raha tha
    flux cannot change suddenly so
    i becomes e/nr(just after the coil is inserted)

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  4. right.. just wanted to clarify the notion that some people have..

    " its not the current that an inductor tries to keep constant.. BUT THE FLUX "

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  5. ^ what's the reason for this? Why would it try to ONLY keep the flux const.? why not any other physical quantity?

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  6. Aise thodi na hota hai.its not chemistry.koi toh reason hoga.

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  7. ya true but that may be not in jee syllabus
    and if u want details u can search in the google

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  8. you dont get answer to a specific question on google.most of the results give u the basic concept given in every book.u rarely find an answer to a particular question if it is not so famous/popular.i tried for many things in past,all in vain.
    anyway,if u find anything,do give me the link.

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  9. (probably) the general notion is that the magnetic field in an area cannot change suddenly. this is wrong.

    the true statement is that the magnetic FLUX thru an area cannot change suddenly. this is out of JEE syllabus but 'a little extra knowledge' never goes waste!

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