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Practice Exams

  1. Jul 29, 2012 #1
    These exams are merely help for studying for the final in this class. Completing them will not give me any credit whatsoever or affect my grade in the course. The only problem is that our instructor did not give us answers to the tests so we have no idea whether or not we worked the problem correctly. If someone could provide the answers to these problems, not the work that goes along with it, I would be forever grateful. If you need to see an attempt at the solutions before you can give me JUST THE ANSWERS. Then I will upload a PDF for each exam of my attempt at the solutions.
     

    Attached Files:

  2. jcsd
  3. Jul 30, 2012 #2

    Mark44

    Staff: Mentor

    Yes, we need to see an attempt first, according to the rules of PF (to see the rules, click the Rules button near the top of the window).
     
  4. Jul 31, 2012 #3
    EXAM SS09

    Problem 1:
    In = -1 A
    Rth = 10 Ω

    Problem 2:
    Voc = 1.25 V
    Rth = 7.5Ω

    Problem 4:
    0 < t < t0
    VL(t) = 15e-1000tV

    t > t0
    VL(t) = 10e-20000t

    Problem 5:
    Vout = 0V

    Problem 6:
    I3 = 4/3 - 8/3j A

    Vz = 80 + 40j V

    Problem 7:
    Zeq = 10 + ω(-10,000j + 1x10-62)-1

    Not sure how to graph it.... could use some help here.

    Problem 8:
    iavg(t) = -10/3 A
    ieff = 17.5 A

    Problem 9:
    a) Vs(t) = 100√2cos(ωt)

    b) Is = 0.857∠-30.97° A

    c) 85.7∠-30.97° VA

    d) pF = 0.857

    e) z = -818.33Ω

    Problem 10:
    zL = 5 + 3j Ω

    Pmax = 367.65 - 220.6j VA
     
  5. Jul 31, 2012 #4
    EXAM SS10

    Problem 1:
    Using Mesh Currents:
    I1 clockwise in bottom left area.
    I2 clockwise in bottom right area.
    I3 clockwise in top area.

    Vx = 5Ω*I3
    VB - VA = 2V
    VA - VC = VX
    VC = 25Ω*I2
    VA = -10Ω*I1
    VB = 20Ω(I1 - I2)
    I2 = 0.2VX + I3

    Problem 2:
    Vth = 13.33V
    Rth = 8.33Ω

    Problem 3:
    Vc(t) = 7.59 - 7.59e-50,000t
    Vc(t) = 7.59e-50,000t

    Problem 4:
    Vout(t) = Vin(t)/2 - 2.5

    Problem 5:
    a) iavg(t) = 5A
    b) Ieff = 10/√3 A
    c) 500/3 W

    Problem 6:
    S = 0.77 - 1.15j

    Problem 7:
    a) 1 W
    b) 1.28 W
    c) 0.781
    d) C = 45.1μF

    Problem 8:
    C = 40μF
    R = 12.5Ω
    Pmax = 1.25W
     
    Last edited: Jul 31, 2012
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