일반물리학 2 — Electric Fields: Problem 31

31 In Fig. 22-37, the three particles are fixed in place and have charges \(q_1 = q_2 = +5e\) and \(q_3 = -2e\). Distance \(a = 3.00 \text{ mm}\). What are the (a) magnitude and (b) direction (relative to the positive direction of the \(x\) axis) of the net electric field at point \(P\) due to the particles?