Recent content by Michael 37

  1. M

    Testing to see if the vector field could be a magnetic field.

    Is the reason for Fϕ=Fz=0 because in the F function, there are no ∅ or z components? So now all that is left is Fr = (a/r) cos ∅ so do i need the divergence of that (in other words do i differentiate that with respect to r?) And if it = 0, it may be a magnetic field and if it doesn't = 0...
  2. M

    Testing to see if the vector field could be a magnetic field.

    Homework Statement By considering its divergence, test whether the following vector field could be a magnetic field: F=(a/r) cos∅ r Where a is constant. NOTE( the 'r' has the hat symbol ontop if it, unit vector i think) Homework Equations You may use that is cylindrical...
  3. M

    Electricity circuit question, amplitude resistor?

    Due to my severe lack of understanding of circuits as you have probably identified, do you think we should maybe move on to the other parts of the question and hopefully I will be capable of understanding how they work?
  4. M

    Electricity circuit question, amplitude resistor?

    Y=1/Z so Y = 1/7-1.2i. You then said potential is E*Y*z so my potential across my resistor is then : = ((E)(7))/(7-2.1i)? I am struggling to find how I am going to get the amplitude across the resistor. Sorry for being slow at this but I can't see where we are going with this. Thanks
  5. M

    Electricity circuit question, amplitude resistor?

    I just realized that my individual I values were wrong. I multiplied E by the impedance instead of dividing by it. To be perfectly honest I have no idea about the above message but I will try to follow what you are saying and see where I get. Is there not a formula that gives me voltage...
  6. M

    Electricity circuit question, amplitude resistor?

    Done! :) Total current I = E/Ztotal = E/(-1.2i + 7) then multiplying by it's conjugate yields: I total = ( (E)(7 + 1.2i) ) / 50.44 I for the individual componants: For capacitor I = -29.5iE I for Inductor I= 28.3iE I for Resistor I= 7E. What I then did was sum the individual I values and...
  7. M

    Electricity circuit question, amplitude resistor?

    Oh yes my mistake. Ztotal = -1.2i + 7. Maybe this is me just being an idiot but E is Electric potential or voltage, which we do not have. This is where I keep getting lost. I am obviously wrong but to get the flowing current, we need to know the voltage. We don't have that info yet. All we have...
  8. M

    Electricity circuit question, amplitude resistor?

    Hi. I fixed the impedances and found the total complex impedance to hold a value of: -29.5i + 28.3 + 7 = 35.3 - 29.5i = Z total. but if I were to use ohms law to find the voltage amplitude like part A wants me too would the following be correct: Ohms Law: Zr = Vo/Io = R. Therfore Io = Z/R =...
  9. M

    Electricity circuit question, amplitude resistor?

    1) Complex Impedance (C.I) of capacitor = 1/(i)(w)(C) where w=2pif. Therefore plugging it ---> 1/(i)(2pi)(45)(120E-6) = 1/i(29.5) 2) C.I of Inductor = iwL therefore plugging in yields ---> i(2pi)(f)L = (i)(2pi)(45)(100E-3) = i9pi...
  10. M

    Electricity circuit question, amplitude resistor?

    This is frustrating. When I use the complex impedance formula for a capacitor to be (1)/(iwC) I get a total circuit complex impedance to be = ((0.042)/(i0.0339)) + 7. The when I use the other capacitor formula for complex impedance -(i)/(wC) I get the total complex impedance of the circuit to =...
  11. M

    Electricity circuit question, amplitude resistor?

    Yes, the complex impedance of a capacitor is (1/(iwC)) and the Complex impedance of an Inductor is iwL. So I could calculate the individula complex impedances of both comfortably.
  12. M

    Electricity circuit question, amplitude resistor?

    Hi gneil, Yes I know how to calculate complex impedance. I think I am pretty comfortable doing so. Is that needed for this particular question? I was thinking that Z should be the complex impedance but that still leaves me with two unknowns whatever equation I use? I wouldn't be too familiar...
  13. M

    Electricity circuit question, amplitude resistor?

    Homework Statement The ac circuit has 3 components in series: a Capacitor C=120μF, an Inductor L=100mH, and a resistor R=7Ω. A) Find the amplitude of the voltage across the resistor R in the LCR circuit below, when operated at a frequency of 45 Hz? B) What is the phase difference...
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