Question

A +9 B Four small spheres (A, B, C, and D), each of mass m=0.02g, are arranged as shown on the figure, all located a distance d=3.00cm from a point P. Spheres A, B, and C each carry a charge of +5.00nC, while sphere D carries a charge of -5.00nC. d +9 d a) When all the spheres are fixed at their positions, -9 what is the electric field E and electric potential V at point P? D b) What is the total electric potential energy of the +9 system (all four spheres) at that time? c) Sphere D is then released from its initial position (while the other spheres remain fixed), and begins to move toward point P. What is its speed at the moment it arrives at point P? #C

Answer 1

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PAGE Electric potential at point P, v + 2 2 "To d + 9 4t God 4TGod YtGod 2 q Yo God 11 2x 9% 109 x 5 x 10 9 3x102 V 2 30 x 10² V 3000 Votts b) Total electrue potential energy of system, U , bet DC- AD = A B = BC 3 - ده ده کل J२d distance (using U= + (-2)(a) -q (q) 4IT to (52d) + 9(2) 411 6 (Sad) 4T to 18 d) + (+ q | 4776o (20) (-4) (2) 416 (20) + (%) Чле (Us a)

Kinetic energy mond Electric potential energy -7 I mua 225 X10 let 2 n 2x 225x10 0.02 x 10-3 2x 225x 107 sxlos 225 x 10-2 2 | 225x100 v 15 x 10 m/see v- 1.5 m/see speed of I when it arrives at P = 1.5 wupper