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i_island0
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1. suppose a long solenoid is connected to a DC source and after a long time steady state has reached. And suddenly an iron rod is inserted in the solenoid along its axis. Obviously, self inductance of the solenoid will increase by some factor. [One can assume some resistance of of the solenoid if required].
MY question is:
(a) what happens to the magnetic field at the center of the solenoid.
(b) what happens to the magnetic flux through an infinitesimally small area at the center of solenoid.
My answer to them are:
1(a) magnetic field reduces - as current will reduce.
1(b) flux doesn't change. - as lenz's law says that induced emf is such that it opposes the cause. so flux shouldn't change.
2. suppose a long solenoid is connected to a constant current source and after a long time steady state has reached. And suddenly an iron rod is inserted in the solenoid along its axis. Obviously, self inductance of the solenoid will increase by some factor. [One can assume some resistance of of the solenoid if required].
MY question is:
(a) what happens to the magnetic field at the center of the solenoid.
(b) what happens to the magnetic flux through an infinitesimally small area at the center of solenoid.
My answer to them are:
2(a) magnetic field reduces - as current will reduce. [but how can current reduce if we are using a constant current source across an inductor (i am confused here)].
2(b) flux doesn't change. - as lenz's law says that induced emf is such that it opposes the cause. so flux shouldn't change.
Can some one comment of both the answers and correction please if i am saying something wrong.
MY question is:
(a) what happens to the magnetic field at the center of the solenoid.
(b) what happens to the magnetic flux through an infinitesimally small area at the center of solenoid.
My answer to them are:
1(a) magnetic field reduces - as current will reduce.
1(b) flux doesn't change. - as lenz's law says that induced emf is such that it opposes the cause. so flux shouldn't change.
2. suppose a long solenoid is connected to a constant current source and after a long time steady state has reached. And suddenly an iron rod is inserted in the solenoid along its axis. Obviously, self inductance of the solenoid will increase by some factor. [One can assume some resistance of of the solenoid if required].
MY question is:
(a) what happens to the magnetic field at the center of the solenoid.
(b) what happens to the magnetic flux through an infinitesimally small area at the center of solenoid.
My answer to them are:
2(a) magnetic field reduces - as current will reduce. [but how can current reduce if we are using a constant current source across an inductor (i am confused here)].
2(b) flux doesn't change. - as lenz's law says that induced emf is such that it opposes the cause. so flux shouldn't change.
Can some one comment of both the answers and correction please if i am saying something wrong.