On planet Tehar, the free-fall acceleration is similar as that on Earth, however there is as well a strong downward electric field which is uniform close to the planet's surface. A ball of 1.99 kg having a charge of 5.00 µC is thrown upward at a speed of 20.1 m/s. It strikes the ground after an interval of 4.10 s. Determine the potential difference among the starting point and the top point of the trajectory?
The three charges are on the y-axis. A -2.3 C charge, q1, is at the origin and the other unknown charge, q2, is at y = 2.0m. A third charge, q3, of -4.6 C is positioned at y = -2.0m, where it is in electrostatic symmetry with the other two charges. Determine the charge on q2?