Several problems in electrostatics.
1. A tiny ball (mass = 0.015 kg) carries a charge of -20 µC. What electric field (magnitude and direction) is needed to cause the ball to float above the ground?
2.At a distance r1 from a point charge, the magnitude of the electric field created by the charge is 284 N/C. At a distance r2 from the charge, the field has a magnitude of 112 N/C. Find the ratio of the distances.
3.Two charges are located on the x axis: q1 = +2.0 µC at x1 = +4.0 cm, and q2 = +2.0 µC at x2 = -4.0 cm. Two other charges are located on the y axis: q3 = +6.0 µC at y3 = +5.0 cm, and q4 = -2.0 µC at y4 = +7.0 cm. Find the net electric field (magnitude and direction) at the origin.
N/C ° (measured counter clockwise from the x axis)
4.A rectangle has a length of 2d and a height of d. Each of the following three charges is located at a corner of the rectangle: +q1 (upper left corner), +q2 (lower right corner), and -q (lower left corner). The net electric field at the (empty) upper right corner is zero. Find the magnitudes of q1 and q2. Express your answers in terms of q.
5.A spherical surface completely surrounds a collection of charges. Find the electric flux through the surface if the collection consists of each of the following.
(a) a single +3.0 10-6 C charge
(b) a single -2.6 10-6 C charge
(c) both of the charges in (a) and (b)