When a proton enters a region where an electric field is present, with the initial velocity ?⃗ v → will always move: a along the field line, in the positive direction of the line. b. along the field line, in the negative direction of the line. c. from the point with positive potential to the point with negative potential. d. from the point with negative potential to the point with positive potential. and. as described in both (a) and (c).

QUESTION 5 A thin rod has a non-uniform charge per unit length given by 10) = a x, where a= 45. 0 nC/m, is distributed along the x axis from x +2.00 cm to x = +8.00 cm. If the electric potential at infinity is taken to be zero, wnat is the electric potentiai at the point P on the x-axis at x=15.0 cm? O A. 49.1 mV O B. 2.70 kVv O C. 243 V O D. None of the given options O E. 250 V

1. A disk of radius R has positive charge Q distributed uniformly across its surface. The disk lies flat in the xy-plane, and the z-axis intersects the disk at its center. Z Q x y (a) Determine the electric potential at all points on the z-axis. Assume that the potential goes to zero infinitely far away from the disk. (b) From the potential you found in Part (a), determine the electric field at all points on the z-axis. Make sure that your electric field points in the correct direction above and below the disk.

7. 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 42.0 cm, and the point (A) is located half way between 9₁ and 92. Find the electric potential at point (A). Let q1 -1.20 µC, 92 -3.50 µC, and 93 +4.30 μC. = V ssf60 svo f60 ssf60 ssf60 ssf60 ssf60 s F 91 92 1958 1958 1958 19. ss0 s 160 ssf60 ssf60 ssf60 ssf60 ssf60 ƒ60 ssf60 ssf60 ssf60 ssf60 ssf60 ssf60 ssf6ðę 0 ssf60s ·ssf60 ssf60 sc 60 ssf60 ss. ss150 ssf60 ssf " f60 ssf60 ssf60 ssf60 ssf6