Laura Lombardini, A
p112s09 Due Wed, Feb 18, 2009 at 23:30 Physics 112: General Physics II Section 1 Set 3
CA ID 2718 PA
12. [2pt] A spherical surface completely surrounds a collection of charges. Find the electric ux through the surface if the collection consists of a single +3.05 106 C charge. 13. [2pt] A vertical wall (5.55m x 2.77m) in a house faces due east. A uniform electric eld has a magnitude of 142N/C. This eld is parallel to the ground and points 32.2 north of east. What is the electric ux through the wall? 14. [3pt] Two spherical shells have a common center. A 1.23 106 C charge is spread uniformly over the inner shell, which has a radius of 0.0430m. A +6.47 106 C charge is spread uniformly over the outer shell, which has a radius of 0.172m. Calculate the magnitude of the electric eld at a distance (measured from the common center) of 0.212m.
1. [2pt] A metal sphere has a charge of +7.94C. What is the net charge after 5.84 1013 electrons have been placed on it? 2. [2pt] Object A is metallic and electrically neutral. It is charged by induction so that it acquires a charge of 2.82 106 C. Object B is identical to object A and is also electrically neutral. It is charged by induction so that it acquires a charge of +2.82 106C. Calculate the dierence in mass between the charged objects.
3. [2pt] In a vacuum, two particles have charges of q1 and q2 , where q1 = +4.00C. They are separated by a distance of 15. [4pt] Two charges are placed between the plates of a par0.247m, and particle 1 experiences an attractive force of 3.27N . allel plate capacitor. One charge is +q1 and the other is q2 = +5.13C. The charge per unit area on each plate has a magniWhat is the magnitude of q2 ? tude of = 1.49 104C/m2 . The force on q1 due to q2 equals 4. [2pt] Two tiny conducting spheres are identical and carry the force on q1 due to the electric eld of the parallel plate charges of -21.0C and +50.1C. They are separated by a capacitor. What is the distance r between the two charges? distance of 2.34cm. What is the magnitude of the force that 16. [4pt] Two identical small insulating balls are suspended by each sphere experiences? separate 0.203m that threads are attached to a common point 4 5. [2pt] A charge of -2.92C is xed at the center of a compass. on the ceiling. Each ball has a mass of 8.08 10 kg. Initially Two additional charges are xed on the circle of the compass the balls are uncharged and hang straight down. They are then (radius = 0.116m). The charges on the circle are -3.95C at given identical positive charges and, as a result, spread apart the position due north and +4.84C at the position due east. with an angle of 34.2 between the threads. Determine the What is the magnitude of the net electrostatic force acting on charge on each ball. the charge at the center?
Department of Physics and Astronomy, SUNY Geneseo . . . . . . . . . . . . . . . . . . . . . . CAPA c msu
6. [3pt] A point charge of -0.733C is xed to one corner of a square. An identical charge is xed to the diagonally opposite corner. A point charge q is xed to each of the remaining corners. The net force acting on either of the charges q is zero. Calculate the magnitude of q. 7. [2pt] At a distance r1 from a point charge, the magnitude of the electric eld created by the charge is 262N/C. At a distance r2 from the charge, the eld has a magnitude of 138N/C. Calculate the ratio r2 /r1 . 8. [2pt] Two charges are placed on the x axis. One charge (q1 ...