Selected Solutions, Physics 104 Exam File

 Electric force, fields, and dipoles  1. 12cm 3. c and d 5. 53o below the horizon 7. 2.6mN/C, 150o 9. 5.8MN/C, to the left 13. 24.3N, neg. x 19. 2´10-11C×m, 0.36N/C, positive y-direction Electrical potential and capacitance  1. 15V/m at -63o 3. a) and b)  5. a) V/m2 7. 47MV/m at 17o, 94000N, 18MV, 36kV 9. 0V, 120kV/m, 1.2×1010V/m, ditto 11. zero, 540kV, 54MV/m 17. -800V, x=0 wall, 0.24m 21. 3.9´10-11m, 0.75mJ 23. properties of space, scalars 25. -7500V 29. 0, +540V, -54kV/m 31. 149.2V, 147.8V, 70V/m, 74V/m, 0 33. 120MN/C at 0o, 5.941MV, 5.939MV, 100MV/m 35. 0.8mV, 38nC 37. 37micron, 1.3mC, 73kV/m 37. 0.034m2, 27nC, no sparking 39. 0.89pF, 75kV, 67nC, 1.1pF Electric current, resistance, circuits 1. 4 resistors in parallel 3. 36microC, 3.6ms, 1.4m2 5. 1800J, 12eV, 1.9´ 7. V/2, 3R 9. Voltage decreases to 71% of its value  11. 2V/m, 39nW m 17. It decays exponentially toward zero.  21. 3.0s, 0.76mC, 1.2´ 10-8C× m 23. decaying, decaying, increasing, constant Magnetism  1. East to West 3. -5x10-13T, +10x10-13T, 7x10-13T 5. North 7. 240MA, 1.1micron/s 9. 20microT, 24microN 11. 0.0017T, 250mN, toward top of page Magnetic Induction  1. Counter-clockwise 3. to the right of the page 5. bottom of the page, counterclockwise 7. toward top of page, out of the page 9. 2800N, 6.3MA-m2 11. 14s, clockwise 13. 23mT into page, 9.8mN toward top of page 15. 14s. clockwise 17. counter-c'wise, 5.5s, 0.94mT 19. 0A, 0.60A; 12V, 0V; 1.3ms; 0.52A 21. 12mA, 80ms, 21ms AC Circuits  1. 156V, 7.6ohm, 350microF 3. 0.35A, 0.25A; 12W, 6W; 0.26H 5. 6.45V 7. 6.1A, 163V, 1000W 9. 14W, 10.7V, 1.9A, 1.3A 11. 9.8W, 490mH, 5.1mF 13. 1.5nH, 1.5nF, 1W, 0.03W 15. 22000 17. 990kV, 6GW, 3GW, 1:6400; 30MA 19. 400, 0.010A, 0.014A, 2.4W Geometric Optics  1. 22ms 3. 22o from the vertical, 36cm 5. 7.6o, 82.4o, 1.487 7. 2.01´ 108m/s, 1.52´ 10-11s, 79o 9. -1.5m, 0.25, virtual 11. The first three 13. 9.3cm 15. 60m, 1.5 17. -1.3m, -0.77D, 13cm 19. +4.0D, 2.3cm 23. 12.5cm, 8.3cm 25. 0.40m, 0.67m Physical Optics  1. interference, accommodation, reflecting material has larger refractive index 3. F, T, F 5. 41.8o 11. Soap bubble, black: all light is poorly reflected, 92nm, none 13. "soap bubble", white, 183nm, 370nm 15. 0.4m, 8, three 17. bubble, black, 98nm, none 19. 53o, 7, 7 21. 25o, 9cm Relativity  1. 0.9999c, 5000lb, 0.35cm, 6.1moc2 3. TTFTT 5. No, no. Consider the centripetal acceleration. 7. 2.3, 0.83 (ux=-0.83c), 42m 9. 0.995c, 9cm, 8.3cm 11. c 13. 10.0005m, 8000.4kg, 3.6×1016J, 0.4kg 15. 2.1´ 17. -0.99995c, 7000kg, 0.25cm, 6.1moc2 19. 0.42m/s2 21. -0.65c, 1.25´ 23. 1.6´ 10-28kg, 104MeV, no Modern Physics  1. lp=9.7mm, 4% 3. 2.8 5. 3, 2.9 7. 2.14eV, 1.14´ 15. -2.40eV, -2.00eV, -1.60eV, -1.20eV 17. 6, 3.3´ 10-25N× s, 76.5mm 19. 1.1´ 29. lower limit: 1.7fm, 0.13fm 31. 35m/s, 6.3´ 10-11m 45. 0.1587u, 147.8Mev, 0.134MeV, released 47. 8´ 10-16m, 10fm 49. 1.94u, 1807MeV, 84MeV 53. 103MeV given off, 181MeV 55. 14hr