{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

Ch18-h4-solutions - liu(ql744 Ch18-h4 chiu(56565 This...

Info icon This preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
This print-out should have 29 questions. Multiple-choice questions may continue on the next column or page – find all choices before answering. 001 (part 1 of 6) 5.0 points Conventional current flows through the ring shown in the figure below in such a way that if you stand at location A on the + x axis and look towards the ring, current appears to be flowing clockwise. The ring lies in the yz plane, encircling the x axis. x z y A B C D E F What is the direction of the magnetic field due to the ring at A? 1. ˆ B A = 0 , - 1 , 0 2. ˆ B A = 1 , 0 , 0 3. ˆ B A = 0 , 1 , 0 4. ˆ B A = 0 , 0 , 1 5. ˆ B A = - 1 , 0 , 0 correct 6. ˆ B A = 0 , 0 , - 1 Explanation: Given the direction in which the current is traveling around the ring, we can use the right hand rule to find that the magnetic field must point along the - x axis. Therefore the correct choice for point A is ˆ B A = - 1 , 0 , 0 . 002 (part 2 of 6) 5.0 points At B? 1. ˆ B B = 0 , - 1 , 0 2. ˆ B B = 0 , 1 , 0 3. ˆ B B = 1 , 0 , 0 correct 4. ˆ B B = 0 , 0 , - 1 5. ˆ B B = 0 , 0 , 1 6. ˆ B B = - 1 , 0 , 0 Explanation: At any point in the plane of the ring and inside the ring, the magnetic field is pointing through the ring along the - x axis. At any point in the plane of the ring but outside of the ring, like B, D, E, and F, the magnetic field lines will be wrapping back around toward the positive x axis to travel back through the ring again. So at these points the correct choice for the direction of the magnetic field is ˆ B = 1 , 0 , 0 . 003 (part 3 of 6) 5.0 points At C? 1. ˆ B C = 0 , - 1 , 0 2. ˆ B C = 0 , 0 , 1 3. ˆ B C = 0 , 0 , - 1 4. ˆ B C = 1 , 0 , 0 5. ˆ B C = - 1 , 0 , 0 correct 6. ˆ B C = 0 , 1 , 0 Explanation: See the explanation for part 1. 004 (part 4 of 6) 5.0 points At D? 1. ˆ B D = - 1 , 0 , 0 2. ˆ B D = 0 , 1 , 0 3. ˆ B D = 0 , 0 , - 1
Image of page 1

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

View Full Document Right Arrow Icon
4. ˆ B D = 0 , - 1 , 0 5. ˆ B D = 0 , 0 , 1 6. ˆ B D = 1 , 0 , 0 correct Explanation: See the explanation for part 2. 005 (part 5 of 6) 5.0 points At E? 1. ˆ B E = 0 , 0 , 1 2. ˆ B E = 0 , 0 , - 1 3. ˆ B E = 0 , 1 , 0 4. ˆ B E = 1 , 0 , 0 correct 5. ˆ B E = - 1 , 0 , 0 6. ˆ B E = 0 , - 1 , 0 Explanation: See the explanation for part 2. 006 (part 6 of 6) 5.0 points At F? 1. ˆ B F = 0 , 0 , - 1 2. ˆ B F = - 1 , 0 , 0 3. ˆ B F = 1 , 0 , 0 correct 4. ˆ B F = 0 , - 1 , 0 5. ˆ B F = 0 , 1 , 0 6. ˆ B F = 0 , 0 , 1 Explanation: See the explanation for part 2. 007 (part 1 of 2) 10.0 points A loop of wire carries a conventional current of 0 . 8 A. The radius of the loop is 0 . 1 m. Calculate the magnitude of the magnetic field at a distance of 0 . 31 m from the center of the loop, along the axis of the loop. Use μ 0 4 π = 1 × 10 - 7 T · m / A . Correct answer: 1 . 45444 × 10 - 7 T. Explanation: Here we use the formula for the magnetic field due to the loop of current: B = μ 0 4 π 2 I A ( r 2 + R 2 ) 3 / 2 , where A is the area of the loop, R is the radius of the loop, and r is the distance of the observation point from the center of the loop. We have B = 2(1 × 10 - 7 T · m / A)(0 . 8 A) π (0 . 1 m) 2 ((0 . 31 m) 2 + (0 . 1 m) 2 ) 3 / 2 = 1 . 45444 × 10 - 7 T . 008 (part 2 of 2) 10.0 points What would the magnitude of the magnetic field be at the same location if there were 100 loops of wire in a coil instead of one loop? Correct answer: 1 . 45444 × 10 - 5 T.
Image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern