p240f11+midterm+3-3-solutions

p240f11+midterm+3-3-solutions - Form listed as VERSION on...

Info iconThis preview shows pages 1–4. Sign up to view the full content.

View Full Document Right Arrow Icon
Version 3 Page 1 Form # listed as VERSION # on bottom of each page Physics 240 Third Exam Fall 2011 1. Last Name:____________________ First Name:_____________________ 2. Please circle your discussion instructor and section below: Instructor Time Section David Gidley 9-10 100 David Winn 10-11 200 David Winn 11-noon 300 3. Special Scantron Instructions: a) Bubble in UNIQ-NAME in “last name” field b) Bubble in 8 digit UM student ID number—this is critical c) Bubble in Form #=version# (critical) and section number d) Print your name in shaded upper right signature box 4. There are 20 multiple choice problems worth 1 points each for a total of 20 points. Choose the one best answer and transfer it to the scantron sheet. You must mark the correct answer on the scantron sheet to get credit for the problem. There is no penalty for guessing, so be sure to enter an answer for every question even if it is just a best guess. 5. At the end of the exam hand in both your scantron and exam booklet in separate piles set up by the proctors. 6. This is a closed book, 90 minute exam. Turn off and put away all electronic devices. You may use a calculator and three 3”x5” note card or equivalent. k = 1/4πε 0 =9x10 9 Nm 2 /C 2 ε 0 = 8.85x10 -12 C 2 /Nm 2 e = 1.6x10 -19 C 1 eV= 1.6x10 -19 J μ = micro =10 -6 g = 9.8 m/s 2 m e = 9.1 x 10 -31 kg M P =1.67 x 10 -27 kg μ 0 = 4π x 10 -7 Tm/A
Background image of page 1

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

View Full DocumentRight Arrow Icon
Version 3 Page 2 1. A wire is wrapped 250 times around a ferromagnetic nickel cylinder of length 10 cm and radius 2 cm and a relative magnetic permeability of 100. When a current of 45 mA runs through the wire what fraction of the magnetic field inside the nickel comes from atomic currents? A) 9% B) 100% C) 1% D) 45% E) 99% 2. Two very long parallel wires carry currents I and 3I and are located at x = -2 m and x = +2 m respectively. Where along x could we place another parallel wire with current 2I pointing down such that the force on this third wire is zero? A) x = -3 m B) x = 0 m C) x = +3 m D) x = -1 m E) x = +1 m X (m) -5 -3 -4 0 -1 1 3 4 5 I 3I
Background image of page 2
Version 3 Page 3 3. When a permanent iron magnet is heated to a glowing red-hot temperature: A) it loses its magnetism B) nothing happens C) the N and S poles reverse polarity D) it becomes an induced magnet E) its magnetic permeability increases 4. 15 seconds after closing the switch the current flowing through the battery is: A) 17 A B) 3 A C) 30 A D) 45 A E) 12 A 5. A cylindrical region of radius R contains a uniform electric field, parallel to its axis, with magnitude that is exponentially decaying with time, 0 () t Et Ee τ = . The circulation of the magnetic field, B dl
Background image of page 3

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

View Full DocumentRight Arrow Icon
Image of page 4
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 01/30/2012 for the course PHYS 240 taught by Professor Winn during the Fall '11 term at University of Michigan.

Page1 / 14

p240f11+midterm+3-3-solutions - Form listed as VERSION on...

This preview shows document pages 1 - 4. Sign up to view the full document.

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