Voltage drop over an independent current source?

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nickadams
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Homework Statement



I am supposed to give a thevenin equivalent circuit to the one posted in the picture.

Homework Equations



V=IR
KVL: "voltage drops around a closed loop sums to zero
KCL: "current into a node equals current out of a node"

The Attempt at a Solution



The part I'm confused about is the node and wire I've circled in red. I know since the wire coming down from the node is connected to ground that the bottom of the wire has V=0... I also know that the voltage drop across the current source is = Voc... but Voc has the higher voltage on top which would mean the current source is forcing current to flow from low voltage to high voltage...

Can someone please help me understand?
 
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  • Hand-drawn circuit schematic: 10V source on the left in series with a 10 ohm resistor on top, a 5 ohm resistor down the middle to ground, and a 1A current source circled in red on the right branch, with Voc marked across its terminals and polarity + on top and - below.
    circuit.JPG
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nickadams said:
The part I'm confused about is the node and wire I've circled in red. I know since the wire coming down from the node is connected to ground that the bottom of the wire has V=0... I also know that the voltage drop across the current source is = Voc... but Voc has the higher voltage on top which would mean the current source is forcing current to flow from low voltage to high voltage...
Current sources will make their specified current flow regardless of the potential difference. That's how they can supply power to a circuit. If you think about it, voltage sources do the same thing, moving charges from a lower potential to a higher potential.
 
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gneill said:
Current sources will make their specified current flow regardless of the potential difference. That's how they can supply power to a circuit. If you think about it, voltage sources do the same thing, moving charges from a lower potential to a higher potential.

Okay! That makes sense; thank you.