In the figure four particles form a square with edge length a = 4.39 × 10-2 m. The charges are q1 = q4 = 2.92 × 10-15 C and q2 = q3 = q. (a) What is q if the net electrostatic force on particle 1 is zero? (b) Is there any value of q that makes the net electrostatic force on each of the four particles zero?

Two foam blocks, each with a charge of 8 microcoulombs (1 µC = 10-6 C), are both held in place 8 cm apart in the east-west direction. A foam ball with a charge 38 µC is placed 55 cm north of the foam block on the west side. Then, the ball is released, and it moves as a result of the electrostatic force produced in this system. What is the net electrostatic force (magnitude and direction) experienced by the foam ball?

In the figure three identical conducting spheres form an equilateral triangle of side length d = 28.6 cm. The sphere radii are much smaller than d and the sphere charges are qA = -2.55 nC, q = -4.50 nC, and qc = +6.98 nC. (a) What is the magnitude of the electrostatic force between spheres A and C? The following steps are taken: A and B are connected by a thin wire and then disconnected; B is grounded by the wire, and the wire is then removed; B and C are connected by the wire and then disconnected. What now are the magnitudes of the electrostatic force (b) between spheres A and C and (c) between spheres B and C? (a) Number i (b) Number i (c) Number i Units Units Units < <

In the figure four particles are fixed along an x axis, separated by distances d = 3.80 cm. The charges are q₁ = +4e, q2 = -e, 93 = +e, and 94 = +12e, with e = 1.60 × 10-19 C. What is the value of the net electrostatic force on (a) particle 1 and (b) particle 2 due to the other particles? (a) Number i (b) Number i Units 1 Units d 2 d 3 d 4