A circular path of radius \(0.20\,\mathrm{m}\) has uniform tangential induced field \(0.30\,\mathrm{V\,m^{-1}}\). Find the emf around the path.
Question 3
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A uniform magnetic field changes at \(4.0\,\mathrm{T\,s^{-1}}\) inside a circular region. Find the induced electric field magnitude at \(r=0.10\,\mathrm{m}\) inside the region.
Question 4
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A changing magnetic field is confined to radius \(R=0.30\,\mathrm{m}\) and changes at \(2.0\,\mathrm{T\,s^{-1}}\). Find \(E\) at \(r=0.60\,\mathrm{m}\).
Question 5
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Explain why an induced electric field can exist even where there is no wire.
Question 6
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Why is an induced electric field from changing magnetic flux nonconservative?
Question 7
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Inside a radius \(R\) where \(dB/dt\) is uniform, derive \(E=(r/2)|dB/dt|\).
Question 8
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Outside a changing-field region of radius \(R\), derive \(E=(R^2/2r)|dB/dt|\).
Question 9
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A changing magnetic field into the page is increasing. What is the direction of the induced electric field lines?
Question 10
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A changing magnetic field out of the page is increasing. What is the direction of the induced electric field lines?
Question 11
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For a circular path inside a changing-field region, if \(r\) doubles, how does \(E\) change?
Question 12
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For a circular path outside a changing-field region, if \(r\) doubles, how does \(E\) change?
Question 13
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At \(r=R\), show that the inside and outside circular-field formulas agree.
Question 14
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A circular electron orbit of radius \(0.050\,\mathrm{m}\) lies inside a region where \(B\) changes at \(8.0\,\mathrm{T\,s^{-1}}\). Find the induced electric force magnitude on an electron.
Question 15
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A circular path of radius \(0.25\,\mathrm{m}\) has emf magnitude \(0.50\,\mathrm{V}\). Find the average tangential induced electric field.
Question 16
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A changing field is uniform inside radius \(R\). Sketch verbally how \(E(r)\) varies from \(r=0\) to far outside the region.
Question 17
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Explain why voltage between two points is path-dependent for an induced electric field.
Question 18
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A circular region has \(B(t)=B_0+kt\) into the page. Determine whether the induced electric field direction is clockwise or counterclockwise for \(k>0\).
Question 19
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For \(r<R\), derive the acceleration magnitude of a charge \(q\), mass \(m\), released at radius \(r\) by a changing magnetic field \(dB/dt\).
Question 20
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Use Faraday's law to explain why induced electric field lines cannot be purely radial around the axis of a changing uniform magnetic field.