A uniform axial magnetic field exists only within radius R and changes at rate k. At a point at radius r>R, determine the induced electric-field magnitude.
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A uniform axial magnetic field exists only within radius R and changes at rate k. At a point at radius r>R, determine the induced electric-field magnitude.

G1 Physics · Accepted Answer

Only area πR² contributes flux. Thus E(2πr)=πR²k and E=kR²/(2r).