HW 4 - Kapoor (mk9499) homework04 Turner (60230) 1 This...

Info iconThis preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: Kapoor (mk9499) homework04 Turner (60230) 1 This print-out should have 11 questions. Multiple-choice questions may continue on the next column or page find all choices before answering. 001 (part 1 of 2) 10.0 points A charge Q is distributed uniformly along the x axis from x 1 to x 2 . The Coulomb constant is 8 . 98755 10 9 N m 2 / C 2 Which of the following integrals is correct for the magnitude of the electric field at x on the x axis? Assume that x > x 2 > x 1 and k e = 1 4 . 1. None of these 2. integraldisplay x 2 x 1 k e Q ( x 2 x 1 ) x 2 dx 3. integraldisplay x 2 x 1 k e Q ( x 2 x ) x 2 dx 4. integraldisplay x 2 x 1 k e Q ( x 2 x )( x x ) 2 dx 5. integraldisplay x 2 x 1 k e Q ( x 2 x 1 )( x x ) 2 dx correct Explanation: For a continuous charge distribution, dE = k e dq r 2 . Recall that for a uniform linear charge dis- tribution, dq = dx = Q L dx = Q x 2 x 1 dx . Furthermore, the point x is a distance ( x x ) from a charge element dq . Hence integrating from x = x 1 to x = x 2 yields E = integraldisplay x 2 x 1 k e Q ( x 2 x 1 )( x x ) 2 dx . 002 (part 2 of 2) 10.0 points If x 1 = 0 m, x 2 = 5 . 59 m and the charge Q = 3 . 49 C, what is the magnitude E of the electric field at x = 8 . 2 m? Correct answer: 1465 . 59 N / C. Explanation: Let : k e = 8 . 98755 10 9 N m 2 / C 2 , x 1 = 0 m , x 2 = 5 . 59 m , x = 8 . 2 m , and Q = 3 . 49 C . E = integraldisplay x 2 x 1 k e Q ( x 2 x 1 )( x x ) 2 dx = k e Q ( x 2 x 1 )( x x ) vextendsingle vextendsingle vextendsingle vextendsingle x 2 x 1 = ( 8 . 98755 10 9 N m 2 / C 2 ) (5 . 59 m 0 m) (3 . 49 10 6 C) bracketleftbigg 1 8 . 2 m 5 . 59 m 1 8 . 2 m 0 m bracketrightbigg = 1465 . 59 N / C . 003 (part 1 of 4) 10.0 points Consider a disk of radius 3 . 1 cm, having a uniformly distributed charge of +5 . 7 C....
View Full Document

Page1 / 5

HW 4 - Kapoor (mk9499) homework04 Turner (60230) 1 This...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online