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In electromagnetism of parallel magnetic circuits, the reluctance offered for two parallel paths will be _________.
square for each path
half for each path
cube for each path
quarter for each path
half for each path
In magnetic circuits, when two identical reluctance paths are connected in parallel, the total equivalent reluctance of the circuit is halved. This follows the same mathematical principle as resistors connected in parallel in an electric circuit.
In magnetic circuits, when two identical reluctance paths are connected in parallel, the total equivalent reluctance of the circuit is halved. This follows the same mathematical principle as resistors connected in parallel in an electric circuit.
R=╬╝AlтАЛ тАФ Formula for reluctance where l is length, ╬╝ is permeability, and A is cross-sectional area
ReqтАЛ1тАЛ=тИСRiтАЛ1тАЛ тАФ Equivalent reluctance for parallel magnetic circuits
Reluctance is defined as the opposition to magnetic flux, given by R=╬╝AlтАЛ. When two parallel paths of equal reluctance R are provided, the equivalent reluctance ReqтАЛ is calculated as ReqтАЛ1тАЛ=R1тАЛ+R1тАЛ, resulting in ReqтАЛ=2RтАЛ.
Reluctance is analogous to electrical resistance in an electric circuit.
Magnetic flux ╬ж is analogous to electric current I.
Magnetomotive force (MMF) is analogous to electromotive force (EMF) or voltage.
For parallel paths, the total reluctance decreases, thereby increasing the total flux for a constant MMF.
Reduces total circuit reluctance
Increases total magnetic flux carrying capacity
Requires more magnetic material
Increased risk of leakage flux
Transformers with multi-limb cores
Electrical machines (stator and rotor magnetic paths)
The analogy is derived from the Hopkinson's law of magnetic circuits, which mirrors Ohm's law.
Option A, C, and D are incorrect as they do not follow the inverse sum law for parallel components.
B is correct тАФ The total reluctance of two parallel magnetic paths of equal reluctance is half of the individual reluctance value.
Always remember the analogy: MMF тЙИ Voltage, Flux тЙИ Current, and Reluctance тЙИ Resistance. This makes parallel/series circuit problems intuitive.