2. Two point charges q1 = +2 C and q2 = -3 C are fixed in place along the x-axis, as shown. 91 = +2 C 92 = -3 C X = 0 X = a You have in your hand another point charge q, and you want to place it somewhere on the x-axis. But you want to place it at a point where it will stay. That is, you want to place it at a point where it will feel no force due to the fixed charges qi and q2. (Hint: Think about what the force looks like very close to each charge and what it looks like very far away from both charges.)

16. Two point charges qA = +10.0 µC and qB = -40.0 µC and a third particle with unknown charge qC are located on the x axis. The particle qA is at the origin, and qB is at x = 12.0 cm. The third particle is to be placed so that each particle is in equilibrium under the action of the electric forces exerted by the other two particles. a) The diagrams below show a positively charged qC in each of the three possible locations with respect to qA and qB. Draw and label vectors (for example, -->F AB) showing the directions of the forces on all three particles, and circle any of the diagrams in which there are opposing forces on all three charges.

= 32.2 nC. The figure below shows a small, hollow, plastic sphere hanging vertically from a thin, lightweight thread. The sphere has a mass of 7.10 g and a uniformly distributed charge of 91 Directly below it is a second sphere with the same mass, but a charge of 92 = -58.0 nC. (Assume this second sphere is fixed in place.) The centers of the two plastic spheres are a distance d = 2.00 cm apart. 91 92 (a) What is the tension (in N) in the thread? 0.11154376 N (b) The thread will break if the tension in it exceeds 0.180 N. What is the smallest possible value of d (in cm) before the thread breaks? The analysis is the same as in part (a), including the magnitude and direction of the gravitational and electric forces. Note that Coulomb's law depends on the square of the distance d. Use the threshold value of the tension to solve for d. cm

10. Three point-like charges are placed at the corners of an equilateral triangle as shown in the figure. Each side of the triangle has a length of 20.0 cm, and the point (C) is located half way between qı and q3 along the side. Find the magnitude of the electric field at point (C). Let q1 = -1.60 µC, q2 = +2.60 µC, and q3 = +5.20 µC. N/C oof19 00 q3 19.0of19.0of19.oof19 oof19.of of19 0of19 0of19 0of19.oof19 oof of19 0of19 oof19 0

1. Two point sources, one with a charge of -3 nC and the other +9 nC, are placed 3m apart as shown below. A third charge is placed at point P, 4 m to the right of the -3nC source. -3nC 3 m 4 m +9 nC *P a) Find the magnitude and direction of the net field at point P. b) Find a location where the net field is zero (if the negative source is at (0,0) what are the coordinates of this point?) Add it to the diagram and label it O. c) Find the approximate field at a test point M that is 1 km (1000 m) to the right of P d) By what factor will the magnitude of the field change if you move M from 1 km to 3 km away? e) Find the magnitude and direction of the force on each of -1pC test charges placed at M, O, and P.

if an electron is placed near 3 charges, find the speed of the electron after it has been pushed far away. Given q = 2 nc, q2 = 2 nc, q3 = 1 nc. x 1 = 2cm and y equals 2cm 9₁ 92 | X ✓ Election 93