+¾μµC +3μC Charges of 3.0 C are located at x = 0.0, y = 2.0 m and at x = 0.0, y = -2.0 m. Unknown charges, Q, are located at z = 4.0, y = 2.0 m and at z = 4.0, y = -2.0 m. The electric field at the origin, z = 0.0, y = 0.0 m, is 4.0 × 10³ N/C î (in other words in the a direction). Determine the unknown charge Q.

In the future people will only enjoy one sport: Electrodisc. In this sport you gain points when you cause metallic discs hovering on a field to exchange charge. You are an Electrodisc player playing the popular four disc variant. The disks have charges of qA = −8.0 µC, qB = −2.0 µC, qC = +5.0 µC, and qD = +12.0 µC. (a) You bring two disks together and then separate them. You measure the resulting charge of these two disks and find that it is +1.5 µC per disk. Which two disks did you bring together? A and B A and C  A and D B and C B and D C and D?(b) You bring three disks together and then separate them. You measure the resulting charge of these three disks and find that it is +5.0 µC per disk. Which three disks did you bring together? A, B, and C A, B, and D A, C, and D B, C, and D (c) Given the resulting charge of each disk measured in (b) is +5.0 µC, how many electrons would you need to add to a disk of this charge to electrically neutralize it?

A small plastic ball of mass 8.19 × 10³ kg and charge +0.116 μC is suspended from an insulating thread and hangs between the plates of a capacitor (see the drawing). The ball is in equilibrium, with the thread making an angle of 30.0° with respect to the vertical. The area of each plate is 0.01280 m². What is the magnitude of the charge on each plate? 30.0⁰ IN + ++ + ▬▬▬▬▬▬▬▬▬▬▬▬▬▬

Point charges of 20.2 µC and 44.7 µC are placed 0.48 m apart. At what point along the line between them is the electric field zero?   What is the magnitude and direction of electric field halfway between them?   There is no direction because the magnitude of the electric field is zero toward the 20.2 µC charge toward the 44.7 µC charge