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Calculate the reluctance (A/Wb) when the magnetomotive force is 10 A-turns and the flux is 5Wb.
Given: Magnetomotive force (MMF) = 10 A-turns, Magnetic flux (╬ж)=5Wb
Magnetomotive force (MMF) = 10 A-turns, Magnetic flux (╬ж)=5Wb
R=╬жMMFтАЛ
Identify given parameters
From the problem statement, the magnetomotive force is MMF=10┬аA-turns and the magnetic flux is ╬ж=5┬аWb.
MMF=10┬аA-t,╬ж=5┬аWb
Recall the formula for reluctance
Reluctance (R) in a magnetic circuit is analogous to resistance in an electric circuit and is given by Hopkinson's law.
R=╬жMMFтАЛ
Calculate reluctance
Substitute the given values into the reluctance formula: R=510тАЛ=2┬аA/Wb.
R=5┬аWb10┬аA-turnsтАЛ=2┬аA/Wb
A is correct because substituting the given values into Hopkinson's Law yields a reluctance of 2 A/Wb.
Reluctance (R) in a magnetic circuit behaves exactly like Resistance (R) in an electrical circuit, where MMF is analogous to Voltage (V) and Flux (╬ж) is analogous to Current (I) according to Ohm's Law (V=IR).