Voltage across open circuit (very basic question)

So, the voltage equals 0VIn summary, in a normal circuit without any openings, the voltage measured between a resistor and ground will be 0V because according to Ohm's law, the voltage across a resistor is equal to 0V when there is no current flowing. Additionally, in a circuit with an opening, the sum of all voltages (including resistors and openings) will equal the voltage source due to Kirchoff's voltage law. Therefore, the resistor voltage will also be 0V, resulting in the voltage between the resistor and ground being equal to the voltage source.
  • #1
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1
0
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 when I measure the voltage between the resistor?, as in just the wire? I assume 0v, but why?
 
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  • #2
Have you learned Kirchoffs voltage law?

If no, think of that in every circuit the sum of the voltages across resistors and switches equals the voltage soruce. Since there is no current in the circuit, ohms law dictates that U=0V across any resistor. Therfore the sum of all voltages (resistors and openings) equals the voltage source. In this case, resistor voltage equals 0V so voltage source=switch voltage.

Second question: ohms law: U=R*I, and in a short wire R≈0.
 

What is voltage across an open circuit?

Voltage across an open circuit refers to the potential difference between two points in a circuit where there is no complete path for the electrical current to flow.

How is voltage across an open circuit measured?

Voltage across an open circuit can be measured using a voltmeter, which is a device that measures the potential difference between two points in a circuit.

What causes voltage across an open circuit?

Voltage across an open circuit is caused by a break in the circuit, which prevents the flow of electrical current. This can be due to a disconnected wire or an open switch in the circuit.

Is there any voltage across an open circuit?

Yes, there can still be voltage across an open circuit. This is because the potential difference between the two points in the circuit still exists, even though there is no complete path for the current to flow.

What is the difference between voltage across an open circuit and voltage across a closed circuit?

The main difference is that voltage across an open circuit is measured when there is no complete path for the current to flow, while voltage across a closed circuit is measured when there is a complete path for the current to flow. In other words, voltage across an open circuit is the potential difference between two points where there is no flow of current, while voltage across a closed circuit is the potential difference between two points where there is a flow of current.

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