Magnetomotive Force & Magnetic Field Strength - Free MCQ Practice Test

A permeable substance is one through which the magnetic lines of force can pass through easily.

Materials having low retentivity are temporary magnets because they can retain the magnetic strength for only some time.

Moving charges have a magnetic field associated with them because they have magnetic flux lines associated with it.

Magnetic lines of force originate at the north pole and terminate at the south pole hence they are from the north pole to the south pole.

Magnetic force lines emerge at the north pole. Force lines seem to emerge at the north pole because they originate at the north pole.

When a bar magnet is broken into two pieces, it forms two differ bar magnets. This happens because the broken pieces of the magnet forms a separate north and south pole for itself as monopoles do not exist.

when the current flows into the page, the magnetic field is clockwise because of the right hand thumb rule, we orient our thumb into the page and our fingers curl in the clockwise direction.

 when the current flows out of the page, the magnetic field is anti-clockwise because of the right hand thumb rule, we orient our thumb out of the page and our fingers curl in the anti-clockwise direction.

The right hand thumb rule determines the direction of magnetic field in a current carrying conductor. The rule states that when we align our right thumb in the direction of the current and curl our fingers around it, the direction of our fingers is the direction of the magnetic field.

When a conductor carries a certain value of current, the force developed in the conductor, the current in the conductor and the magnetic field in the conductor are mutually perpendicular to each other.