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schematic

simulate this circuit – Schematic created using CircuitLab

Does any current flow from point A to point B?

My guess is no. Because both of those points are connected to a ground symbol by blank wires, they both have potential of 0V.

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    \$\begingroup\$ In order anything to flow there should be a closed circuit. \$\endgroup\$ – Eugene Sh. Sep 26 '17 at 21:26
  • \$\begingroup\$ Simulators hate floating nodes. So you may need to add such wires, or else supply a galvanic connection of some kind. For simulation, anyway. \$\endgroup\$ – jonk Sep 26 '17 at 21:29
  • \$\begingroup\$ If you don't like using a wire, you could use a 1 GH inductor. \$\endgroup\$ – The Photon Sep 26 '17 at 21:30
  • \$\begingroup\$ @ThePhoton Always keep one in a drawer for those special times! \$\endgroup\$ – jonk Sep 26 '17 at 21:44
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    \$\begingroup\$ Two ways to answer that: 1. Current only flows in complete circuits. 2. KCL. \$\endgroup\$ – The Photon Sep 26 '17 at 21:50
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My guess is no. Because both of those points are connected to a ground symbol by blank wires, they both have potential of 0V.

Your guess is right, but your reasoning is incorrect.

In any idealized circuit like this, the potential is equal at all points on the wire, but we still allow that current can flow. Because the wire is modeled to have 0 resistance, it doesn't require any potential difference across it to establish a current.

The reason there is no current in this wire is because of the cut-set form of KCL. If you were to break that wire, there'd be no other connection between the two halves of the circuit. Therefore no complete circuit can form using that wire, and so we know no current is flowing through it even when it isn't broken.

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There is no current flowing in that wire. In fact, it doesn't matter what that "Point B" is connected to -- no current will flow because there are no other connections to establish a path for any current.

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  • \$\begingroup\$ Why should there be another connection for current to flow out of that wire? If you place a earth ground where charge can flow out of, at point A, and point B has a higer potential than point A should there be a current from point A to both B? \$\endgroup\$ – most venerable sir Sep 26 '17 at 21:41

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