iii. Consider another tube, identical and parallel to the first one.
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The second tube has the same magnetic field but in the opposite direction and its centre is placed at y=l,x=z=0 (so that the tubes form opposite sides of a square). Determine the magnetic interaction force F between the two tubes.
Given constants:
Part C. Magnetic straws
Consider a cylindrical tube made of a superconducting material. The length of the tube is l and the inner radius is r with l≫r. The centre of the tube coincides with the origin, and its axis coincides with the z-axis.
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There is a magnetic flux Φ through the central cross-section of the tube, z=0,x2+y2<r2. A superconductor is a material which expels any magnetic field (the field is zero inside the material).
Context question:
i. Sketch five such magnetic field lines, which pass through the five red dots marked on the axial cross-section of the tube, on the designated diagram on the answer sheet.
Context answer:
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Context question:
ii. Find the tension force T along the z-axis in the middle of the tube (i.e. the force by which two halves of the tube, z>0 and z<0, interact with each other).
Context answer:
T=2μ0πr2Φ2