Ampere's Law, Cylinders, Solenoid & Toroid
Two wires with current 3A and 1.5A are enclosed in a circular loop P. Third parallel wire with current 1A is situated outside the loop as shown. All the wires are perpendicular to the plane of the circular loop. The value of around the loop is ( permeability of free space)

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Answer: (c)
- Ampere's law: ; the outside wire does not count.
- The 3 A and 1.5 A currents are opposite: A.
- So the answer is (c).