Science : Ch 13 – Magnetic Effects of Electric Current

Commercial electric motors neglect :

An electron moves with a speed v along positive direction of the x-axis. If a magnetic feld B acts along the positive y-direction, then the force on the electron will act along:

Which of the subsequent is not attracted by a magnet:

Relative strength of magnetic field at a point in the space adjoining the magnet is shown by the:

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

Example of permanent magnet is

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

Which of the following is not attracted by a magnet:

An electron moves with a speed v along positive direction of the x-axis. If a magnetic feld B acts along the positive y-direction, then the force on the electron will act along

The deflection of the galvanometer becomes zero the moment the motion of

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

You are holding the current-carrying wire in your right hand so that your thumb points in the direction of current, then the direction in which your fingers encircle the wire will give the direction of the magnetic feld lines around the wire.explain