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When a loop rotates in a magnetic field, does it have to actually "cut" the field lines in order to have emf induced in it? I mean if the loop is rotating and there is a rate of change of flux in the loop, does this mean that the loop is also "cutting" the field lines? I know if the loop is cutting the field lines, there is a change of flux associated with it at the same time such that motional emf BlvsinΘ= induced emf dΦ/dt.
Consider the middle limb. Suppose it is excited by a dc source and a constant flux is enclosed in the core and no flux is present in the air. Now consider the red loop on the middle limb. If it is tilted at an angle Θ, the flux linking with the loop will change since flux Φ=BAcosΘ. But the loop will not physically "cut" the field lines. Will there be emf induced in the loop if it moves but doesn't physically "cut" the field lines? There is a change in flux associated with the loop but is that sufficient to induce emf in the loop?
Consider the middle limb. Suppose it is excited by a dc source and a constant flux is enclosed in the core and no flux is present in the air. Now consider the red loop on the middle limb. If it is tilted at an angle Θ, the flux linking with the loop will change since flux Φ=BAcosΘ. But the loop will not physically "cut" the field lines. Will there be emf induced in the loop if it moves but doesn't physically "cut" the field lines? There is a change in flux associated with the loop but is that sufficient to induce emf in the loop?
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