posted by .

How long does it take for the current in an circuit with = 150Ω and = 65mH to reach half its final value?

  • Physics -

    i = (V/L)[ 1 - e^(-R t/L) ]
    at t = 0, i = 0
    at t-->oo , i --> V/L
    so when is
    [ 1 - e^(-R t/L) ] equal to 1/2 ?
    when e^(-Rt/L) = 1/2
    ln e^(-Rt/L) = -Rt/L = - .693

    so when
    t = .693 (L/R)

Respond to this Question

First Name
School Subject
Your Answer

Similar Questions

  1. Physics

    Three resistors (14.4 Ω, 21.7 Ω, 14.1 Ω) are connected in parallel across 98 V. What is the total resistance for this circuit?
  2. physics please help!!

    1. A 26.0-Ω resistor, a 12.0-µF capacitor, and a 17.0-mH inductor are connected in series with a 150-V generator. (a) At what frequency is the current a maximum?
  3. physics

    Consider the circuit in the diagram. Let R1 = 51.0 Ω, R2 = 38.0 Ω, R3 = 74.0 Ω, R4 = 16.0 Ω, and V = 84 V. (b) What current flows from the battery?
  4. physics

    A 50 V battery has an internal resistance r. 1 A 50 V r 55 Ω 66 Ω internal resistance What is the value of r?
  5. physics

    Consider the following circuit. 7.3 Ω 3.0 Ω 3.0 Ω 4.5 Ω 1.0 Ω 3.0 Ω 4.5 Ω 19.0 Ω 19.0 Ω 30 V Find the equivalent resistance. Answer in units of Ω

    Consider the circuit in Figure P32.17, taking script e = 6 V, L = 5.00 mH, and R = 7.00 . Figure P32.17 (a) What is the inductive time constant of the circuit?
  7. Physics

    One 10.0 Ω resistor is wired in series with 10.0 Ω resistors in parallel. A 45.0 V battery supplies power to the circuit. What is the total current through the circuit?
  8. Electronics, Physics, Math

    5. A circuit is supplied with 30 VDC and contains three resistors connected in series. The value or R1 is 80Ω, the value of R2 is 1,000Ω , and the value of R3 is 4,200Ω . What is the voltage drop across R2?
  9. physics

    The lightbulb in the circuit shown in the figure has a resistance of 14 Ω and consumes 4.2 W of power; the rod is 1.18 m long and moves to the left with a constant speed of 2.9 m/s . The strength of the magnetic field is 2.2 T …
  10. Physics

    A 120-V rms voltage at 60.0 Hz is applied across an inductor, capacitor and a 100-Ω resistor in series. If the maximum value of the current in this circuit is 1.60 A, what is the rms value of the current in this circuit?

More Similar Questions