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20. || What is the net electric flux through the torus (i.e.. doughnut shape] of FIGURE 324.20? + -1 nC (inside) +100 nC FIGURE EX24.2021. ll What is the net electric flux through the cylinder of FIGURE 531.1411? FIGURE EX24.21 +100 I'lC +1 TIC (inside) 10C|'nC 26. | The conducting box in FIGURE EX24.26 has been given an excess negative charge. The surface density of excess electrons at the center of the top surface is 5.0 X 1010 electrons/m. What are the electric field strengths E, to E, at points 1 to 3? 1 . 2. Closed surface FIGURE EX24.26 FIGURE EX24.2727. I| FIGURE EX24.27 shows a hollow cavity within a neutral conduct tor. A point charge Q is inside the cavity. What is the net electric flux through the closed surface that surrounds the conductor?\f35. || A neutral conductor contains a hollow cavity in which there is a +100 nC point charge. A charged rod then transfers 50 nC to the conductor. Afterward, what is the charge (a) on the inner wall of the cavity. and (b) on the exterior surface of the conductor