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shebbbbo
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4. Consider a coaxial cable consisting of two infinitely thin conducting cylindrical surfaces
with radii R1 < R2. A current I flows in one direction in the inner cable and in the
opposite direction in the outer cable. Using the Amperian loop technique, determine the
magnetic field
a)inside the inner cable : r < R1 ,
b) between the two shells : R1 < r < R2,
c) outside of the wire : R2 < r.
a) I had a go at this one and thought it you place the amerian loop at R1, you would simply get amperes law:
∫B.dL=u0I
B = u0I/(2πR)
but i had a friend who said if you change where the loop is you can show that there is no current and therefore the field goes to zero? I am not sure which is the correct angle to tackle this question.
i would use the same method for b and c, but i would then find some reduction of the B field due to the radius?
thanks for any advice!
with radii R1 < R2. A current I flows in one direction in the inner cable and in the
opposite direction in the outer cable. Using the Amperian loop technique, determine the
magnetic field
a)inside the inner cable : r < R1 ,
b) between the two shells : R1 < r < R2,
c) outside of the wire : R2 < r.
a) I had a go at this one and thought it you place the amerian loop at R1, you would simply get amperes law:
∫B.dL=u0I
B = u0I/(2πR)
but i had a friend who said if you change where the loop is you can show that there is no current and therefore the field goes to zero? I am not sure which is the correct angle to tackle this question.
i would use the same method for b and c, but i would then find some reduction of the B field due to the radius?
thanks for any advice!