A conductor suspended by two flexible wires as shown in the figure below has a mass per unit length of 0.0436 kg/m. x x x x x x + x x x x x x x x Bin (a) What current must exist in the conductor for the tension in the supporting wires to be zero when the magnetic field is 3.70 T into the page? (b) What is the required direction for the current? (We are looking for the direction of the current in the conductor.) O to the left

Consider a short wire of length L, carrying a current I to the left. Define coordinates so that the wire is along the à axis, the current flows in the - direction, the y axis is vertical in the plane of the page and the 2 axis points out of the page. Which of the following expressions is an ap- proximate expression for the magnetic field at a point P on the y axis very close to the wire, i.e. a distance y < L below the mid- point of the wire? 1. B= 2(y2 + L2) O 2. B 0 3. B Hol 2ny Hol 4Vy2 + L² 4. B = Hol 4Ty 5. B = %3D O 6. B=-00 O, B = 47 (y2 + L2) 8. B = 27 Vy? + L2 40IL 2ny? 9. B = 10. B – _ 40! 2ny

Let x=0 be the beginning of the magnetic field.  Express the area (A), and express vw in terms of the area.  Then what is vBw in terms of magnetic flux? The magnetic force on the conducting charges is an EMF, an electromotive force.  Use these to derive the following expression for the EMF:   Please see attachments for details on question and diagram.

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A wire carries a 5.78-A current along the x axis, and another wire carries a 2.18-A current along the y axis, as shown in the figure below. What is the magnetic field at point P, located at x = 4.00 m, y = 3.00 m? 0.138 Use the expression for the magnetic field around a current-carrying wire to find the magnitude and direction of the magnetic field contribution from each of the two currents. UT magnitude direction out of the page y (4.00, 3.00) m

6. A wire with length L carries a constant current of I in the +y direction. See figure. It is in a region of space where the magnetic field is given by: B=-B, y (4) L positive constant. If the magnitude of the magnetic force on the wire is F, find Bo. The knowns are F, I and L. Start with dF = Idl x B I i, where Bo is a thickness = dy I L

a straight, flexible length of copper wire is immersed in a magnetic field that is directed into the page . If the wires current runs at the + x-direction, which way will the wire bend ? which way will the wire bend if the current runs in the -x direction

A cylindrical conductor of radius 10-2 m has a magnetic field H = (4.77x104)(ρ/2 - ρ2/(3x10-2 )) in its surface. What is the total current of the conductor?   QUICKLY