In the figure below, six charged particles surround particle 7 at radial distanc
ID: 1525068 • Letter: I
Question
In the figure below, six charged particles surround particle 7 at radial distances of either d = 1.0 cm or 2d, as drawn. The charges are q_1 = +8e, q_2 = +6e, q_3 = +e, q_4 = +6e, q_5 = +6e, q_6 = +4e, q_7 = +8e, with e = 1.60 times 10^-19 C. What is the magnitude of the net electrostatic force on particle 7? N Did you draw the forces on particle 7 as vectors, with their tails anchored on particle 7? Did you get the directions right? Did you use the Coulomb equation to find their magnitudes? Did you then combine the forces as vectors to get the net force?Explanation / Answer
Force in X direction would be due to:
1, 3 , 4
Fx = kq1q7/r17^2 + kq3q7/r13^2 + kq4q7/r47^2
Fx = kq7 (q1/r17^2 + q3/r13^2 + q4/r47^2)
Fx = 9 x 10^9 x 8 x (1.6 x 10^-19)^2 [8/0.01^2 + 1/0.01^2+ 6/0.02^2] = 1.843 x 10^-27 x 10500
Fx = 1.94 x 10^-22 N
Fy = k q7 [ q2/r27^2 + q5/r57^2 + q6/r67^2]
Fy = 9 x 10^9 x 8 x (1.6 x 10^-19)^2 [ 6/0.01^2 + 6/0.01^2 + 4/0.02^2] = 1.843 x 10^-27 x 130000
Fy = 2.39 x 10^-22 N
F = sqrt [Fx^2 + Fy^2]
F = sqrt [ (1.94 x 10^-22)^2 + (2.39 x 10^-22 )^2] = 3.1 x 10^-22 N
Hence, F = 3.1 x 10^-22 N