Science : Ch 13 – Magnetic Effects of Electric Current

Commercial electric motors neglect :

Which of the subsequent is not attracted by a magnet:

The magnetic field lines:

Magnetic effect of current was identified by:

By which instrument, the presence of magnetic field be resolved?

The nature of magnetic field line passing through the centre of current carrying circular loop is:

When current is parallel to magnetic field, then force experience by the current carrying conductor placed in uniform magnetic field is

In electric motor, to make the coil rotating constantly in the identical direction, current is reversed in the coil after every half rotation by a device called:

The name of the effect being produced by the moving magnet

The commercial motors use a soft iron core on which the coil is wound because

A coil of many circular turns of wire wrapped in the shape of a cylinder

The change in magnetic feld lines in a coil is the cause of induced electric current in it. Name the underlying phenomenon.

Which of the following is not attracted by a magnet:

The law states that if the forefinger indicates the direction of the magnetic field and thumb shows the direction of motion of conductor, then the middle finger will show the direction of induced current

Two magnetic feld lines never intersect because the resultant force on a north pole at any point can only be in