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magnetic field line is an imaginary line showing magnetic energy between a north and south pole .
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How are magnetic field lines described?
Magnetic Field Lines Show Magnitude and Direction:When the lines of the magnetic field are close together the magnetic field is strong. In a region where the line density is high, one says that it has great intensity or strength. Technically, the density of lines is proportional to the magnitude of the field.The direction that magnetic field lines are oriented provides the information on the direction of the field, with the convention that the lines have arrows drawn so the lines exit from the North pole of a permanent magnet, or equivalently, the arrows point in the direction that the North end of a compass needle would point if placed on the line.More Information:Magnetic field lines do not really exist any more than electric field lines exist, but both are extremely valuable representations of the strength and direction of magnet (or electric) fields. (Pictures of field lines are human creations to help understand fields, but the pictures of field lines that are correctly drawn do provide a faithful representation of the mathematical description of the field.)When one says a magnetic field is "strong" one does not mean that it exerts a great force on another magnetic object. Strength of a magnetic field is defined in terms of torque, not force. Here is how.Magnetic Vector Field Definition:If a magnetic field exists at a certain point, then one characterizes it with a strength and direction. Indeed, one can do this at all points and know the magnitude and direction of the field at all points. Because vectors have magnitude and direction, we can associate a vector with the magnetic field at any point and that is why one says that a magnetic field is a vector field.Magnetic Field Direction:We define strength or magnitude of the field using the classic behavior that we see when we use a compass. The field exerts a torque on the compass needle to orient it. One end of the compass is marked "North" because, in the absence of any other field, the compass needle points to the "North" geographic pole of the Earth. Using this definition, when a compass is brought near a permanent magnet, the North end of the compass is said to point towards the South end of the magnet. (North poles attract South poles.) This pointing direction can be mapped out in the whole space around the bar magnet, orienting the compass not just flat or horizontal, but in all directions so as to determine which way the magnetic field points for all positions in the space around the permanent magnet. (This works equally well for electromagnets, but we describe it for the most simple situation.)Magnetic Field Strength:The field direction of at each point, as described above, is the direction the North end of the compass needle points when there is zero torque on the needle. If one turns the needle so it is perpendicular to the field direction, then the needle experiences maximum torque. That torque measures the strength or magnitude of the field. Thus, once you set the strength scale by assigning one value of the field strength for one particular compass, you can map out the field strength at all points with the same compass and you get the magnitude and direction of the magnetic field everywhere.Magnetic Field Lines:The above process produces a vector field meaning that at every point in space one could draw an small arrow with a magnitude and direction indicating the field. Such a drawing produces a picture a bunch of arrows in the space around the magnet representing the magnetic field. That is a perfectly good representation of a vector field.One can also create a line representation of a vector field, magnetic, electric or other. For the magnet above, if you start at a point on the North end of the magnet and draw a line in the direction of the arrow, you immediately encounter another arrow. At the point of the new arrow you continue drawing the line in the direction of that arrow, until you get to the next arrow which gives the next direction and on and on. Basically, if you start at the North end of the magnet and draw a line in a direction that follows the directions of the arrows, that line ends up at the south end of the magnet. One can the pick a new starting position on the surface of the magnet and repeat the process. Doing this over and over produces a whole set of lines which eventually fills the entire space around the magnet.The set of lines drawn are not the magnetic field lines. But, each of the lines drawn does follow a magnetic field line. That sounds odd, but to fairly represent the strength of the field, one has to have one more condition applied that determines how many lines are drawn. That condition is that the number of lines in any region of space is proportional to the strength of the field in that region. That requires some additional rule because the number or density of lines won't communicate the field strength if one just draws lines wherever one likes.Density of Magnetic Field Lines:When using field lines to represent a vector field (electric or magnetic or whatever) one needs the information of both magnitude and direction and the individual lines only give direction. So, convention is that the number of lines that you draw in any particular region of space is proportional to the strength (magnitude) of the field in that region. That is hard to do. Fortunately, magnetic field lines have a special property that makes this easier.Magnetic field lines never begin or end.The lines in a picture of a bar magnet makes it look like lines exit the North end and enter the South end and they do, but they keep going through the interior and come out the opposite end forming closed loops. Usually the part of the loops inside the magnet are not drawn, but they exist. It is clearer for electromagnets where the inside is visible in the drawing.Drawing Lines:The technical aspects of drawing the lines is too tricky to explain in detail, but here is a simple and correct approach.First, decide how many lines are to be drawn. More is better, but let us suppose 100 for now. That means that all 100 must come out from the parts of the magnet deemed to be North and into the parts identified as South. That includes the ends and the sides and all regions of the surface where lines may go in or out. Draw more lines in the region where strength of the field at the surface is high and fewer out of regions where the strength is low. You have arranged the lines with the right density when putting your imaginary compass into a region with some density of lines will produce a maximum torque corresponding to the field strength. This all sounds a lot easier than it is.They form complete loops.
Does an electromagnetic wave repel from a magnet?
when magnetic line opposite to the magnetic line of the electromagnetic wave, so it can be repel from each other. it is only theorytically based.And depend on my thinking. i do not no it in practical
What shape is magnetic field produced when current is passed through the wire?
it is called the thumb rule right hand curled means flux line thumb means direction of current. there will be a reversal of flux.
What is the function of an electrical coil in a basic circuit?
There are a couple of examples that come to mind where there is a coil in a circuit. One is, the coil is used as a choke to block harmonics from going down the electrical line. Another example of a coil in the line is the coil in a magnetic contactor. When this coil is energized the contacts of the magnetic contactor close.
Rank of miet gondia in India?
Miet is among the line of best engineering college...
Best description of a magnetic field line?
A magnetic field line shows the direction a compass needle would point
Choose the best description of a magnetic field line.?
A magnetic field line shows the direction a compass needle would point.
Choose the best description of a magnetic field line AMagnetic field lines always point north BA magnetic field line shows the direction a compass needle would point CMagnetic field lines?
From that list, I'll have to go with 'B'.
Do magnetic field line complete loops?
no
How does a tangent at any point on the magnetic field line show the direction of magnetic field at that point?
This is true for any contiguous function, not just magnetic fields.
Is magnetic field line scalar or vector quantity?
Vector.
What is a property of a magnetic field?
One property of a magnetic field is that its divergence is zero. That means that a magnetic field line is always a loop and that the net magnetic field coming out of or going in to an enclosed surface is always zero. The result of this is that there are no magnetic monopoles, at least none discovered. Theories, however, do abound.
What is the invisible force around a magnet called?
Have you ever seen a magnet? Did you see the field? There you go. While you can't see the field itself directly, you can see the effects of the field if you use iron filings or something like that; they'll line up with the magnetic field lines
Earths magnetic field can make a magnet out of an iron bar by causing the magnetic domains to?
Line up in the same direction
Which direction does magnetic fields flow?
I think it is a mistake to refer to magnetic field 'flowing. Magnetic fields just are, they can change, and these disturbances might move in space, but the field itself does not flow. That being said, and assuming you meant to ask in which direction a magnetic field points the answer is that a magnetic field points towards the south pole of a magnet and away from the north pole. A magnetic field cannot be divergent (i.e. there are no sources) and any field line must be closed.
What is inductive current?
Induction: Uses electrical energy to create a magnetic field and the magnetic field restores energy back to the line when it collapses.Electrical Theory, Tom Hernry, pp26
What would happen if field lines crossed?
Then, at some point, the field would go into two directions simultaneously, which doesn't make much sense. The magnetic field lines form continuous closed loops.The tangent to the field line at a point represent the direction of the net magnetic field B,at that point.The magnetic field lines do not intersect,if they did, the direction of the magnetic field would not be unique at the point of intersection.
