A plastic rod 1.9 m long is rubbed all over with wool, and acquires a charge of -7e-08 coulombs. We choose the center of the rod to be the origin of our coordinate system, with the x-axis extending to the right, the y-axis extending up, and the z-axis out of the page. In order to calculate the electric field at location A = < 0.7, 0, 0> m, we divide the rod into 8 pieces, and approximate each piece as a point charge located at the center of the piece. (a) What is the length of one of these pieces? = 2375 ✔m (b) What is the location of the center of piece number 8? .83125j m. *1 (c) How much charge is on piece number 8? (Remember that the charge is negative.) -8.750-9 ✔coulombs x j zero magnitude (d) Approximating piece 8 as a point charge, what is the electric field at location A due only to piece 8? E = -46.63471-55.3788j N/C (e) To get the net electric field at location A, we would need to calculate E due each of the 8 pieces, and add up these contributions. If we did that, which arrow above would best represent the direction of the net electric field at location A? 9

A plastic rod 1.9 m long is rubbed all over with wool, and acquires a charge of -7e-08 coulombs. We choose the center of the rod to be the origin of our coordinate system, with the x-axis extending to the right, the y-axis extending up, and the z-axis out of the page. In order to calculate the electric field at location A = < 0.7, 0, 0> m, we divide the rod into 8 pieces, and approximate each piece as a point charge located at the center of the piece. (a) What is the length of one of these pieces? = 2375 ✔m (b) What is the location of the center of piece number 8? .83125j m. *1 (c) How much charge is on piece number 8? (Remember that the charge is negative.) -8.750-9 ✔coulombs x j zero magnitude (d) Approximating piece 8 as a point charge, what is the electric field at location A due only to piece 8? E = -46.63471-55.3788j N/C (e) To get the net electric field at location A, we would need to calculate E due each of the 8 pieces, and add up these contributions. If we did that, which arrow above would best represent the direction of the net electric field at location A? 9