Two long wires carrying current

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The discussion revolves around calculating the line integrals of magnetic field (∫B⋅ds) and electric field (∫E⋅ds) for two long wires carrying currents I1 and I2 in opposite directions. For the case where I1 and I2 are both 1A, the magnetic field integral evaluates to zero, while for I1 at 1A and I2 at 0A, it equals μ0. The participants express uncertainty about calculating the electric field integral, particularly in relation to Faraday's Law, which involves the rate of change of magnetic flux. A hint is provided that the nature of the currents (constant or time-varying) does not affect the calculation of magnetic flux. The conversation emphasizes the need for clarity on the magnetic flux (Φ) in the given scenario.
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Homework Statement


Two long wires carrying current I1 and I2 in opposite directions pass through a closed path S as shown in the picture.
What are the values of ∫B⋅ds and ∫E⋅ds if:
i) I1=I2=1A
ii) I1=1A and I2=0A?

physexam1q5.png


Homework Equations


Ampere's Law: ∫B⋅ds=μ0I
Faraday's Law: ∫E⋅ds=-dΦB/dt

The Attempt at a Solution


For i, ∫B⋅ds=μ0(I1-I2)=μ0(0)=0
For ii, ∫B⋅ds=μ0(I1)=μ0(1)=μ0

Is these correct? But I have no idea of finding ∫E⋅ds

Please help.
 
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What about the righthand side if you knw the currents are constant ?
 
scrubber said:
Faraday's Law: ∫E⋅ds=-dΦB/dt

The Attempt at a Solution


But I have no idea of finding ∫E⋅ds
Please help.
What is Φ for your situation? Hint: it doesn't matter whether the currents are constant or time-varying.
 
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