Advertisements
Advertisements
प्रश्न
State briefly the modern views on magnetism.
Advertisements
उत्तर
The molecular theory of magnetism was a considerable step forward but later there came an electrical explanation for the magnetism of atoms and this had wider applications. We have already seen that magnets can be made by an electric current. Atoms contain particles of electricity called electrons that move in orbits about a central nucleus. These electrons behave like an electric current in a single turn of wire and so create a magnetic field. More importantly, the electrons are also spinning like tops and this adds further magnetism to the atom.
The apparently non-magnetic substances are classified as either diamagnetic or paramagnetic respectively. We shall explain these terms very briefly before going on to deal with the strongly magnetic or ferromagnetic substances.
APPEARS IN
संबंधित प्रश्न
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
What is a natural magnet? State two limitations of a natural magnet.
In following figure, draw at least two magnetic field lines between the two magnets.
(a) 
In following figure, draw at least two magnetic field lines between the two magnets.
(b) 
Figure. shows a bar magnet placed on the table top with its north pole pointing towards south. The arrow shows the north-south direction. There are no other magnets or magnetic materials nearby.
Indicate by crosses, the likely positions of the neutral points.
Figure. shows a bar magnet placed on the table top with its north pole pointing towards south. The arrow shows the north-south direction. There are no other magnets or magnetic materials nearby.
What is the magnitude of the magnetic field at each neutral point? Give a reason for your answer.
Draw diagram showing the arrangement of the lines of force for two magnets in line, with unlike poles facing one another.
If the key in the arrangement is taken out (the circuit is made open) and magnetic field lines are drawn over the horizontal plane ABCD, the lines are
The magnetic field lines are stronger near the ______ and it diminishes as you go away from it.
Define magnetic field lines of force.
