Physics

A circuit consists of a self inductor of L=0.003 H in series with a resistor R1=5 Ohm. Parallel to these is a resistor R2=10 Ohm. A battery of V0=9 volt is driving the circuit.

Current has been running for 10 minutes.

(a) How much energy (in Joules) is now stored in the self-inductor.

(b) How much power (in Watt) is then generated by the battery into the circuit? (ignore internal resistance of the battery).

The connection to the battery is now broken (so that the battery is not connected to the circuit anymore).

(c) How long will it take (in seconds) for the current through R1 to be reduced by 50%?

(d) How long does it take (in seconds) till the energy stored in the self-inductor has been reduced by 50%?

(e) How long will it take (in seconds) for the current in R2 to be reduced by 50% (compared to the highest value right after the battery is disconnected)?

  1. 👍 0
  2. 👎 0
  3. 👁 242
  1. plz help.....!

    1. 👍 0
    2. 👎 0
  2. I can tell you a) & b)
    a) Assuming after 10 min I=Imax then
    I1=V/R1 and so the energy is 1/2*L*I1
    b) I=V/Req (Req=(R1*R2)/(R1+R2)) So P=I*V

    1. 👍 0
    2. 👎 0
    posted by s
  3. Thnx :) a) n b) are correct ! plz some one for c), d) n e) parts ???

    1. 👍 0
    2. 👎 0
  4. For c) & e):For broken connection of V then Req is R1+R2 so the equation is :
    Imax/2=Imax*e^((-Req/L)*t) and Imax is the Imax from before the connection with the V was broken so Imax=V/R where R=(R1*R2)/(R1+R2)

    1. 👍 0
    2. 👎 0
    posted by s
  5. I still can't get the solution for d if i manage to get it i'll post it

    1. 👍 0
    2. 👎 0
    posted by s
  6. can u plz tell the answers in numerals for time in parts c) n e). I am unable to solve it correctly !

    1. 👍 0
    2. 👎 0
  7. 0.0001386 both. Spent a little time and put the equation in Wolfram alpha it's online calculator and it's very helpfull in general

    1. 👍 0
    2. 👎 0
    posted by s
  8. thnx c n e are correct !

    1. 👍 0
    2. 👎 0
  9. plz lemme knw the b) part when u are able to figure out !

    1. 👍 0
    2. 👎 0
  10. d)since you have find a) then first you should find what the current is for the half energy 0.00486/2=0.00243 so 0.00243=1/2*0.003*I^2 so I=1.27279.the max current in the self inductor was i=9/5=1.8A so the equation is 1.27279=1.8*e^(-(15/0.003)*t)(R=(5+10)Ù because now the connection with v is broken)so t=0.0000693135

    1. 👍 0
    2. 👎 0
  11. Can somebody help with Problem: Displacement Current please?

    I thought the formula is:
    (1.25663706*10^-6*0.04*0.2*0.0705)/(2*pi*0.05^2)

    However, I am not getting the correctr answer.

    1. 👍 0
    2. 👎 0
    posted by FLu
  12. FLu the formoula is (ì0*I)/(2*pi*r) and ì0=4*pi*10^-7

    1. 👍 0
    2. 👎 0
  13. Thanks Anonymous!

    Do you have by any chance the answer for Problem:

    Opening a Switch on an RL Circuit
    b) and c)

    I could figure out a)V_0/R_1
    the other one seems more complicated.

    Can you help please?

    1. 👍 0
    2. 👎 0
    posted by FLu
  14. FLu b) is the equation
    I0*e^((-(R1+R2)/L)*t) I had no luck with the others

    1. 👍 0
    2. 👎 0
  15. Many thanks Anonymous!

    I got d) 100

    Opening Switch on an RL Circuit:
    b) seems in a way easier as most of the letters are not accepted only R1, R2 and V0.

    Did somebody managed it yet?

    1. 👍 0
    2. 👎 0
    posted by FLu
  16. a and d please

    1. 👍 0
    2. 👎 0
    posted by dd
  17. dd, I have provided a and b already just have a look above.

    Anyone for c) please?

    1. 👍 0
    2. 👎 0
    posted by FLu
  18. Did somebody found c) yet please!?

    1. 👍 0
    2. 👎 0
    posted by My
  19. Sorry meant a and d. b) was provided by Anonymous.

    If anybody knows c), thanks in advance!

    1. 👍 0
    2. 👎 0
    posted by FLu
  20. Yes, please answer c) please!

    1. 👍 0
    2. 👎 0
    posted by Ur
  21. c) please!

    1. 👍 0
    2. 👎 0
    posted by Lora
  22. c) Anyone?

    1. 👍 0
    2. 👎 0
    posted by Gema
  23. Anyone for c) guys please?

    1. 👍 0
    2. 👎 0
    posted by FLu
  24. Was someone successful with c)?

    1. 👍 0
    2. 👎 0
    posted by My
  25. for C)... divide the b) by 2

    1. 👍 0
    2. 👎 0
  26. PLEASE NUMERICAL ANSWERS FOR A) AND B)

    1. 👍 0
    2. 👎 0
    posted by Anony
  27. Thanks Supraconductor.
    I could not figure it out. Is it this:

    V_0*e^(R_1+R_2)

    Thanks in advance!

    1. 👍 0
    2. 👎 0
    posted by FLu
  28. Having problems with c) is well, was somebody able to come up with the expression?

    1. 👍 0
    2. 👎 0
    posted by My
  29. Expression for c) please?

    1. 👍 0
    2. 👎 0
    posted by Haet
  30. I tried it out now with the hint of Supraconductor but could not figured out. Did somebody manage it please?

    1. 👍 0
    2. 👎 0
    posted by Ula
  31. c) please anyone!

    1. 👍 0
    2. 👎 0
    posted by Terry
  32. Please c)?

    1. 👍 0
    2. 👎 0
    posted by Ur
  33. c)0.0001386

    1. 👍 0
    2. 👎 0
    posted by hmmmm
  34. Thanks hmmmm, I meant Problem:
    Opening a Switch on an RL Circuit
    Do you have c)?

    1. 👍 0
    2. 👎 0
    posted by Ur
  35. Anyone for Problem:

    Opening a Switch on an RL Circuit: c)?

    Thanks.

    1. 👍 0
    2. 👎 0
    posted by FLu
  36. Finally c)(V_0*(R_1+R_2))/R_1

    1. 👍 0
    2. 👎 0
  37. (Part c for RL circuit)

    1. 👍 0
    2. 👎 0
  38. Great many thanks Anonymous!

    1. 👍 0
    2. 👎 0
    posted by FLu
  39. Please tell RL Circuit I2 I3 for b and c
    ASAP

    1. 👍 0
    2. 👎 0
    posted by P

Respond to this Question

First Name

Your Response

Similar Questions

  1. Physics 112

    A battery is connected in series with a R = 0.26 Ω resistor and an inductor, as shown in the figure below. The switch is closed at t = 0. The time constant of the circuit is τ = 0.10 s, and the maximum current in the circuit is

    asked by juan p on March 30, 2014
  2. Physics

    A certain circuit consists of an inductor of 50 mH in series with a resistor of 130 Ω. At one moment, the current in the circuit is 12 A, and decreasing. How long will it take for the current to fall to 4.8 A? Answer in units of

    asked by Ayo on April 7, 2016
  3. Circuits

    I need to calculate the voltage through the resistor and the voltage through the inductor of an RL series circuit for different frequencies. The voltage of the source is 2.5 V. The inductor is at the top and has an inductance of

    asked by Heather on March 24, 2012
  4. Circuits

    I need to calculate the voltage through the resistor and the voltage through the inductor of an RL series circuit for different frequencies. The voltage of the source is 2.5 V. The inductor is at the top and has an inductance of

    asked by Heather on March 24, 2012
  5. Physics

    In a series circuit, a generator (1400 Hz, 12.0 V) is connected to a 15.0- resistor, a 3.80-ìF capacitor, and a 5.70-mH inductor. Find the voltages across (a) the resistor, (b) the capacitor, and (c) the inductor.

    asked by Kelli on November 12, 2011
  6. Physics

    In a series circuit, a generator (1400 Hz, 12.0 V) is connected to a 15.0- resistor, a 3.80-μF capacitor, and a 5.70-mH inductor. Find the voltages across (a) the resistor, (b) the capacitor, and (c) the inductor.

    asked by Kelli on November 11, 2011
  7. 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? 2.A series circuit contains only a resistor and an inductor. The

    asked by linds on March 21, 2012
  8. Circuits

    I have to calculate the voltage across the resistor of an rlc circuit where the 4.7nF capacitor is in parallel with the .200 H inductor for different frequencies (starting with 1000 Hz) They appear at the top of the circuit and

    asked by Heather on April 9, 2012
  9. physics

    In a series circuit, a generator (1254 Hz, 13.8 V) is connected to a 15.5-Ω resistor, a 4.25-µF capacitor, and a 5.32-mH inductor. Find the voltage across each circuit element. VR = VC = VL =

    asked by linds on March 20, 2012
  10. physics

    An inductor (L=440mH), a capacitor (C=6.00μF), and a resistor (R=440Ω) are connected in series. A 75.0Hz ac generator produces a peak current of 255mA in the circuit. a) What is the impedance of the circuit? Answer in units of

    asked by Anne on March 6, 2015

More Similar Questions