Question #103572

A mild steel ring has a mean circumference of 500 mm

and a uniform cross-sectional area of 300 mm2

.

Calculate the m.m.f. required to produce a flux of

500 µWb. An airgap, 1.0 mm in length, is now cut in

the ring. Determine the flux produced if the m.m.f.

remains constant. Assume the relative permeability

of the mild steel to remain constant at 220.

and a uniform cross-sectional area of 300 mm2

.

Calculate the m.m.f. required to produce a flux of

500 µWb. An airgap, 1.0 mm in length, is now cut in

the ring. Determine the flux produced if the m.m.f.

remains constant. Assume the relative permeability

of the mild steel to remain constant at 220.

Expert's answer

The magnetomotive force can be expressed in terms of flux and magnetic reluctance as

where the magnetic reluctance is

Therefore, for the ring without a gap the MMF is

When we have the airgap, the reluctance changes:

where the length of the steel ring will be, of course, 1 mm less than in the previous case.

Calculations give us the answer of

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Assignment Expert26.06.20, 13:26Dear Varun Bhutada, Questions in this section are answered for free. We can't fulfill them all and there is no guarantee of answering certain question but we are doing our best. And if answer is published it means it was attentively checked by experts. You can try it yourself by publishing your question. Although if you have serious assignment that requires large amount of work and hence cannot be done for free you can submit it as assignment and our experts will surely assist you.

Varun Bhutada16.06.20, 08:58An air-gap between two pole pieces is 20 mm in length and the area of the flux path across the gap is 5 cm2. If the flux required in the air-gap is 0.75 mWb. Find the mmf necessary.

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