What is Open circuit: Definition and 60 Discussions

Open-circuit voltage (abbreviated as OCV or VOC ) is the difference of electrical potential between two terminals of a device when disconnected from any circuit. There is no external load connected. No external electric current flows between the terminals. Alternatively, the open-circuit voltage may be thought of as the voltage that must be applied to a solar cell or a battery to stop the current. It is sometimes given the symbol Voc. In network analysis this voltage is also known as the Thévenin voltage.
The open-circuit voltages of batteries and solar cells are often quoted under particular conditions (state-of-charge, illumination, temperature, etc.).
The potential difference mentioned for batteries and cells is usually the open-circuit voltage. The open-circuit voltage is also known as the electromotive force (emf), which is the maximum potential difference when there is no current and the circuit is not closed.
The opposite of an open circuit is a "short circuit".
To calculate the open-circuit voltage, one can use a method similar to that below.

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  1. L

    Current flowing in an open circuit

    1. Consider this diagram. Does the bulb light up? The equation I=V/R tells me no, but if there is a potential difference between the two points, surely current will flow and the bulb will light? As there is nowhere for the electrons to go, I assume it will only light for a very short period of...
  2. A

    Engineering Short vs Open Circuit: Is That Correct?

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  3. Salmone

    I Can current flow in an open circuit?

    I have two related but separated questions: 1. If I have an open circuit connected to a battery, let's say an alkaline battery connected to a straight wire and nothing more, once I connect the battery to this wire there will be for a short time a current in the wire? Since in the battery due to...
  4. F

    Simulate open circuit and short circuit in MATLAB

    Here's my attempt: The results I got are close to the required answer, but there is a question telling: I tried to solve it, but Isc and Vt (in open circuit) are decreasing with the increase of the field current , so I didn't get the right answer. Could someone let me know where is my...
  5. JamesBennettBeta

    Finding the Open Circuit Voltage

    Problem Statement: While KLM points remain connected, the connection between points XY is removed. Calculate the potential difference between points XY in this situation. Relevant Equations: V=IR, KVL
  6. M

    Does Mutual Inductance Affect Voltage in an Open Circuit?

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  7. cianfa72

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  8. H

    Open circuit voltage of an old battery

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  9. A

    Why isn't a capacitor an open circuit?

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  10. H

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  11. ltnghia1304

    How to find the open circuit voltage?

    Homework Statement How can we find the open circuit voltage of this one: Thank you Homework EquationsThe Attempt at a Solution
  12. C

    Open Circuit Termination for Waveguides in High Frequency Labs

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  13. Biker

    What is the impact of an open circuit on voltmeter readings?

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  14. Marcin H

    Engineering Open Circuit Voltage and Short Circuit Voltage

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  15. J

    Engineering Determine the open circuit voltage for VL

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  16. GauravU

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  17. S

    Short circuit current and Open circuit voltage -- Illumination

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  18. P

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  19. J

    Charge transfer between two capacitors in an open circuit

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  20. T

    Open circuit armature voltage of dc machine?

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  21. X

    If current doesn't flow in an open circuit, how are capacitors charged?

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  22. M

    Confused about short circuit and open circuit

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  23. M

    Fuel cell open circuit voltage and pressure of reactants

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  24. I

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  25. T

    Open circuit short circuit (test) TX flux effect

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  26. G

    Engineering How can voltage flow in a open circuit

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  27. L

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  28. I

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  29. C

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  30. C

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  31. K

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  32. Entanglement

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  33. F

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  34. P

    Engineering Synchronous Machines - Open Circuit and Short Circuit Tests

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  35. T

    Engineering How to find voltage in an open circuit

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  36. P

    What is the steady state voltage across the capacitor in this open circuit?

    The problem asks to find the steady state voltage across the capacitor. i attached the circuit (sorry for the poorly drawn and yes, that open part of the branch is supposed to be there) This is a multiple choice question where the answers are: a) 0V b) V_dc/2 c) V_dc/3 d) V_dc e) 2*V_dc...
  37. M

    Open Circuit Problem with Logic Gates

    I wonder how can I make the logic gate read 0V when it is open? For instance, the AND logic gate. If one of its input pin has 5V supply, and the other don't have, the output signal given to me is 5V. How can I make it 0V? Well, theoretically, it should be 0V, but in reality, it appears that...
  38. Y

    Engineering AC circuit with dependant current and voltage source and open circuit element

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  39. S

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    Hi guys, I have recently started to think about basic electronics and realized that I don't know electricity theory at all cause I couldn't answer a few questions asked by my friend. Imagine an open circuit(forum_pic) Wiill there be any current at all. I...
  40. J

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    Hi! Could someone briefly explain the following scenario to me please :) If an open circuit (with the 2 ends named X and Y) hung on a string is swung through an into page magnetic field, what would the emf be? How would that change if you are asked about the voltage 'measured' between X and Y...
  41. R

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  42. Y

    Electric potential in an open circuit

    Hi, I was wondering, if a circuit is open, would capacitors still have a potential difference ? If there is no potential difference, can we say its potential is 0 then obtain a charge equal to 0 for the capacitor's charge ?
  43. T

    Solenoid in open circuit and with glavanometer attached

    1.A student performs an expierment on a soenoid. The solenoid is open circuit in the first instance, the studet then pushes a magnet into one end with a constant force. the second instance, the solenoid is connected to a galvanometer. Using the concept of energy conversion, relate and explain...
  44. J

    Voltage across open circuit (very basic question)

    Vs to R1 to R2 to R3 to ground If there is an opening in the circuit between R1 and R2, why is it that when I measure the voltage between R1 and R2, it equates to the voltage source voltage? Why does the resistor not matter? If the circuit is normal without any opening, what will I get...
  45. Y

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    There is a open circuit like below figure A---------R(10ohm)--------V(10V)-------------B The Voltage between A and B is 10V. The resister do not affect in this circuit. This is what I have learned. But I do not understand why the resistance do not affect to the voltage value. Please...
  46. N

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  47. F

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    Any help appreciated with these! Homework Statement 1. A battery is made up from a series combination of six 1.2 volt nickel cadmium cells supplying a 10ohm load- a) What is the open circuit voltage? b) Ignoring internal resistance, what is the current flowing in each cell? 2. The nickel...
  48. R

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  49. M

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  50. N

    Engineering Understanding Transformer Power Measurements with Open Circuit Experiment

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