Question

A plastic rod 1.5 m long is rubbed all over with wool, and acquires a charge of -9e-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. 1. What is the length of one of these pieces? 2. What is the location of the center of piece number 2? 3. How much charge is on piece number 2?

Answer 1

Answer:

a) I = 0.1875 m

b) r_2 = 0.46875 m

c) q = -1.125*10^-8 C

Step-by-step explanation:

Given:

- The total Length of rod L = 1.5 m

- The total charge of the rod Q = -9 * 10^8 C

- Total section of a rod n = 8

Find:

1. What is the length of one of these pieces?

2. What is the location of the center of piece number 2?

3. How much charge is on piece number 2?

Solution:

- The entire rod is divided into 8 pieces, so the length of each piece would be:

                                      l = L / n

                                      l = 1.5 / 8

                                      I = 0.1875 m

- The distance from center of entire rod and center of section 2 is 2.5 times the section length

                                      r_2 = 2.5*l

                                      r_2 = 2.5*(0.1875)

                                      r_2 = 0.46875 m

- Assuming the charge on the rod is uniformly distributed. The the charge for each section of rod is given by q:

                                      q = Q / n

                                      q = -9 * 10^8 / 8

                                      q = -1.125*10^-8 C