2. Two positive sign charges are separated by a distance r and have a field E on each other. a. If r is doubled then E is b. If qi is doubled then E is c. If qi and q2 are doubled and r is halved then E is

1.  Common static electricity involves charges ranging from nanocoulombs to microcoulombs. (a) How many electrons are needed to form a charge of −9.10 nC? electrons (b) How many electrons must be removed from a neutral object to leave a net charge of 0.520 µC? electrons   2. What net charge would you place on a 412 g piece of sulfur if you put an extra electron on 1 in 1012 of its atoms? (Sulfur has an atomic mass of 32.1.)   4. What is the repulsive force between two pith balls that are 10.0 cm apart and have equal charges of −39.0 nC?-------N   6.How far apart (in mm) must two point charges of 65.0 nC (typical of static electricity) be to have a force of 5.50 N between them?     7. a.What is the direction of this force (away from or toward the +6 µC charge)? away from the +6 µC chargetoward the +6 µC charge ---------mm A test charge of +9 µC is placed halfway between a charge of +6 µC and another of +7 µC separated by 17 cm. (b) What is the magnitude of the force (in N)…

15. Two charges of equal magnitude but opposite signs, Q and - Q, are placed as shown in the figure. Where does the net electric field point to the right? A. at points E and F only B. at points C and D only C. at points A and B only D. at points A, B, E and F only E. at point C only AB+ с D O E F

20. Two charges of opposite sign and equal magnitude Q are held a distance 2a apart as shown in the figure. Determine the magnitude of the electric field at the point P. +0

Two 2.0-kg spheres each carry a charge of 2.0 C. How does FE compare with Fg?a) FE = Fgb) Fg > FEc) FE > Fgd) FE and Fg cannot be compared without knowing the distance between the spheres..

7 How can you tell which charges are positive and which are negative by examining the field lines? The arrows around a positive charge point away from the charge; the arrows around a negative charge point toward the charge The arrows around a positive and negative charge point away from the charges. The arrows around a positive charge point away from the charge; the arrows around a negative charge point toward the charge. The arrows around a positive and negative charge point towards the charges.

2. Two point charges q1 = +2 C and q2 = -3 C are fixed in place along the x-axis, as shown. 91 = +2 C 92 = -3 C X =0 X = a You have in your hand another point charge q, and you want to place it somewhere on the x-axis. But you want to place it at a point where it will stay. That is, you want to place it at a point where it will feel no force due to the fixed charges qi and q2. (Hint: Think about what the force looks like very close to each charge and what it looks like very far away from both charges.)