The switch has been open for a long time then at t 0

Info icon This preview shows page 1. Sign up to view the full content.

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

Unformatted text preview: uniformly throughout its volume, the magnitude of the potential difference |Vb – V0| would 53% A. increase B. decrease ALWAYS START FROM DEFINITION OF POTENTIAL b ∆ V = − ∫ E ⋅ dr 0 C. stay the same Break integral into two pieces a b ∆V = − ∫ E ⋅ dr − ∫ E ⋅ dr 0 conductor: = 0 insulator: 0 a same for conductor & insulator Physics 212 Lecture 29, Slide 9 RL Circuits 1 In the circuit below, V = 6 Volts, R = 10 Ohms, L = 100 mH. The switch has been open for a long time. Then, at t = 0, the switch is closed. What is the time constant for the current through the inductor? 30% A. R/L B. R/2L C. L/R D. 2L/R E. L/2R I 2 I – I1 L L dI1 − ( I − I1 ) R = 0 dt IR = V − L 1 I1 2 L dI1 + IR − V = 0 dt dI1 dt dI1 dI − V + L 1 + I1R = 0 dt dt 2L dI1 + I1R = V dt Strategy: Back to First Principles • The time constant is determined from a differential equation for the current through the inductor. • Equation for current through inductor obtained from Kirchhoff’s Rules τ= " L" 2 L = " R" R Physics 212 Lecture 29, Slide 10 Faraday’s Law A rectangular wire loop travels to the right with constant velocity, starting in a region of no magnetic field, moving into a region with a constant field pointing into the page (shaded rectangle below), and continuing into a region of no magnetic field. Which plot below best represents the induced current in the loop (Iloop) as it travels from the left through these three regions? Note: a positive Iloop corresponds to a counter-clockwise current. Current in...
View Full 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