A ferromagnetic materials core used in transformers should have low hysteresis loss in order to decrease the energy losses and must have high permeability so that it may show a high value of magnetic induction for the given magnetizing field.
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50 Questions
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Which of the following rules is used to determine the direction of the force on a currentcarrying conductor in an electric motor?
Consider the following statements about magnetic field due to a current-carrying solenoid:
(a) The magnetic field inside the solenoid is in the form of parallel straight lines.
(b)The strong magnetic field produced inside the solenoid can be used to magnetise a piece of a magnetic material.
Which of the above statements is/are correct?
Consider the following statements about magnetic field due to a bar magnet:
(a) The field lines inside a bar magnet are directed from its south pole to the north pole.
(b) The magnetic field lines exist only outside the bar magnet.
Which of the above statements is/are correct?
Two coils, A and B, such that A is connected to a battery through a key and B is connected to a galvanometer, are arranged parallel and close to each other. During which of the following duration will the phenomenon of electromagnetic induction be observed?
(a) Two minutes after closing the key.
(b) During the interval the key is taken out.
Consider the following statements about magnetic field due to a current-carrying solenoid:
(a) The magnetic field is uniform inside the solenoid.
(b) One end of the solenoid behaves like the north pole and the other like the south pole of a bar magnet.
Which of the above statements is/are correct?
Consider the following statements about magnetic field due to a current-carrying straight conductor:
The direction of the south pole of a compass needle at a point gives the direction of the magnetic field at that point.
The direction of the magnetic field lines gets reversed if the direction of the current in the conductor is reversed.
Which of the above statements is/are correct?
