Question

ree Charges C ree charges Q Q, Q are on the y-axis as shown orgin, and Q is locted at (o,a). located at ( a),Gs 2 i5 locateal at ㄋ ind the eneray stored in the chage contiquration assemble the three chages) fourth charge,a=t)AL is now brought in from finity/ and placed bn egeax is at a distance s now brouaht in n the K-axis at a distance onent o the net force Ci and & on

Answer 1

Given, Q_1 = QMC, Q_2 = -12MC, Q_3 = 5 MC, a = 10^-2 m work done, W = W_12 + W_23 + W_13 therefore W = k q_1 q_1/r therefore W = k Q_1 Q_2/a + k Q_2 Q_3/a + kQ_1Q_2/2a W = k/a [Q_1Q_2 + Q_2Q_3 + Q_1Q_3/2] doublerightarrow W = 9 times 10^9/10^-2 [(- 8 times 12 times 10^-12) + (-12 times 5 times 10^-12) + (8 times 5 times 10^-12/2)]J dpublerightarrow W = -122.4 J sigma F_y = F_1y + F_2y + F_3y = -F_1 sin theta + F_3 sin theta = sin theta (-kQ_1q/r^2 + kQ_3q/r^2) tan theta = a/d theta = tan^-1 (1/3) theta = 18.435 degree r = squareroot a^2 + d^2 r = squareroot (1)^2 + (3)^2 r = 3.1623 times 10^-2 m \r\n therefore F_y = sin(18.435 degree) kq/r^2 (-Q_1 + Q_3) F_y = 0.31622 times 9 times 10^9 times 2 times 10^-6/(3.1623 times 10^-2)^2 ((-8 times 10^-6) + (5 times 10^-6)) \r\n