Two long wires carrying current

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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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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.