Magnetic field refers specifically to that area around a material that is magnetic or has a certain amount of electric charge associated with it. It is very important to ensure that before a magnetic field is determined, certain conditions have to be checked and only when they match, can this whole process be taken ahead.
Important points to note:
During passage of an electric current via a wire, there is a certain amount of magnetic field that is built up around area of this wire. An experiment with wire, cardboard and iron fillings can depict this. If cardboard is kept a wire with current flowing within it is passed via this cardboard, there are iron fillings that are placed on this cardboard.
With time, a certain magnetic field is developed and these fillings place themselves accordingly. This conglomeration is referred to as flux, and as per magnetic rules, magnetic field is highest in the middle of this magnet, and comparatively lower at the other ends. It is direction of electron flow that determines the position and direction in which flux will follow.
If there is a change in direction of electron flow, it is depicted in direction of flux, since it also undergoes a change in terms of its direction, rather it flows in a reverse direction. To ensure that this magnetic field can be depicted in a correct manner, right-hand rule, or the right-hand screw rule is applied.
A correct application of this rule results in perfect understanding and depiction of the manner of magnetic field and further details can be found from that. While following this screw rule, it can be seen that screw when placed in a horizontal direction is analogous to current’s direction when placed within a conductor.
Hence, when that screw moves in a circular direction, placement of that magnetic flux can be noted.
Effect of magnet on electric currents:
In case of flowing of an electric current, there is a magnetic field that is associated with it. ThisMagnetic field that is formed and its magnitude is clearly dependent on current’s magnitude, while it is the shape of the conductor that determines the field’s nature.
Here are some of the relations that magnetic fields share with surrounding issues:
- When this magnetic field surrounds a conductor:
In such a scenario, both current and strength of magnetic field are proportional to each other. Hence, if one’s value is changed, it will also affect the other in the same proportion. Hence, either magnetic field is doubled or its value is reduced to zero, similar effects will be foundoncurrent’s standards. With a change in the direction of the current, it is the magnetic field’s direction that also undergoes a change.
- When magnetic field is placed against a solenoid:
In case of a solenoid formation, it has to be seen that passage of current via a solenoid helps in creating a magnetic field. It is due to this strength that transformer coils and circuit breakers are produced and the right hand rule is applied for getting best results.
- When magnetic field is taken in regards to a loop:
In case of a loop formation, it can be seen that magnetic lines form a minimal loop where it enters from one end and exits from the other end. Only point worth noting is thatdirection of coil’s field has to be perpendicular in regards to loop’s plane.
- When magnetic field is taken in regards to 2 parallel conductors:
In such a scenario, it can be seen that with currents moving in opposite directions, those conductors that are carrying this current moves in the opposite direction. While, in case of parallel conductors, when currents move in same direction, there is attraction between the current carrying conductors.
It is very important for students to have a detailed understanding of these concepts.