This preview shows pages 1–2. Sign up to view the full content.
This preview has intentionally blurred sections. Sign up to view the full version.
View Full Document
Unformatted text preview: mcconnell (kam2342) oldhomework 09 Turner (60230) 1 This printout should have 12 questions. Multiplechoice questions may continue on the next column or page find all choices before answering. 001 (part 1 of 2) 10.0 points Two spherical conductors (shown in the fig ure below) are separated by a distance large enough to make induction effects negligible. The spheres (with radii 1 . 1 cm and 0 . 9 cm) are connected by a thin conducting wire and are brought to the same potential of 775 V relative to 0 V at r = . 1 . 1 cm . 9 cm Q 1 Q 2 Determine the capacitance of the sys tem. The Coulomb constant is 8 . 98755 10 9 N m 2 / C 2 . Correct answer: 2 . 2253 10 12 F. Explanation: Let : k e = 8 . 98755 10 9 N m 2 / C 2 , R 1 = 1 . 1 cm = 0 . 011 m , and R 2 = 0 . 9 cm = 0 . 009 m . R 1 R 2 Q 1 Q 2 Both spherical conductors are at the same potential V , so V = k e Q 1 R 1 = k e Q 2 R 2 . The charges on the spheres are then Q 1 = V R 1 k e and Q 2 = V R 2 k e . The capacitance of the system is C = Q 1 + Q 2 V = R 1 + R 2 k e = . 011 m + 0 . 009 m 8 . 98755 10 9 N m 2 / C 2 = 2 . 2253 10 12 F . 002 (part 2 of 2) 10.0 points What is the charge ratio Q 1 Q 2 ? Correct answer: 1 . 22222. Explanation: From Eq. 2, Q R , so we have Q 1 Q 2 = R 1 R 2 = 1 . 1 cm . 9 cm = 1 . 22222 . 003 10.0 points A parallel plate capacitor is connected to a battery. + Q Q d b b 2 d b b If we double the plate separation, 1. the capacitance is doubled....
View
Full
Document
 Spring '10
 Turner

Click to edit the document details