2. Find the vector potential for F = xj. 3. Verify directly that G = (AX R) x R/|R|2 is a vector potential for F = = AXR/|R|2. Convince yourself that the corresponding flow line pattern is identical with that in figure 4.17. 4. Verify directly that the field G = -(log (x2 y2)}k is a vector potential for F (2/(x2+ y2)]k X R. Convince yourself that the flow lines of F are the same as for the rotating fluid, but the flow lines for G are vertical as in figure 4.20. G₂ = A Flow lines for (AXR) X R 3 61666 6666 66667 6666 Flow lines for F= AXR Figure 4.17 22999 Figure 4.20 \\ Flow lines for G3 = -IRI2A/2 c r r c v 00000 //////