Electricity and Magnetism Quiz

The magnetic field lines produced by a bar magnet :

• originate from the south pole and end at its north pole

• originate from the north pole and end at its east pole

• originate from the north pole and end at its south pole

• originate from the south pole and end at its west pole

The magnetic field lines :

• intersect at right angles to one another

• intersect at an angle of 45∘ to each other

• do not cross one another

• cross at an angle of 60∘ to one another

The strength of the magnetic field between the poles of an electromagnet would be unchanged if :

• current in the electromagnet winding were doubled

• direction of current in electromagnet winding were reversed

• distance between the poles of electromagnet were doubled

• material of the core of electromagnet were changed

The diagram represents magnetic field caused by a current-carrying conductor which is:

• a long straight wire

• a circular coil

• a solenoid

• a short straight wire

The magnetic field inside a long straight solenoid carrying current:

• is zero

• decreases as we move towards its end.

• increases as we move towards its end.

• is the same at all points.

Which of the following correctly describes the magnetic field near a long straight wire?

• The field consists of straight lines perpendicular to the wire.

• The field consists of straight lines parallel to the wire.

• The field consists of radial lines originating from the wire.

• The field consists of concentric circles centred on the wire.

The back face of a circular loop of wire is found to be south magnetic pole. The direction of current in this face of the circular loop of wire will be :

• towards south

• clockwise

• anticlockwise

• towards north

An electron beam enters a magnetic field at right angles to it as shown in the Figure. The direction of force acting on the electron beam will be :

• to the left

• to the right

• into the page

• out of the page

A current flows in a wire running between the S and N poles of a magnet lying horizontally as shown in Figure below: The force on the wire due to the magnet is directed:

• from N to S

• from S to N

• vertically downwards

• vertically upwards

The current passing through an electric kettle has been doubled. The heat produced will become:

• half

• double

• four times

• one-fourth