Why 10V Between Every Point in Circuit Diagram?

AI Thread Summary
The discussion clarifies that the circuit diagram indicates a consistent 10V between specific points, primarily due to the common connections in the circuit. Voltage is defined as the difference in potential energy across two points, and while resistors do create potential differences, the overall voltage remains the same across certain point combinations. The key takeaway is that while resistors affect local voltage drops, the total voltage between specific pairs, like points 1 and 6, remains 10V. Misunderstandings arise when considering combinations that do not include common points. The explanation resolves confusion about voltage measurements in the circuit.
goomer
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Please look at the third circuit diagram from the link below

http://www.allaboutcircuits.com/vol_1/chpt_2/7.html

It says that there should be 10V between every point in the diagram. But shouldn't there be a difference in voltage value between points 1 and 2 and points 3 and 4? There's a resistor between points 3 and 4.

My thinking is that if V=IR and there's a resistor between 3 and 4, it should have a different voltage than between points 1 and 2, which doesn't have a resistor between it.

Please explain why I am wrong...
 
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goomer said:
Please look at the third circuit diagram from the link below

http://www.allaboutcircuits.com/vol_1/chpt_2/7.html

It says that there should be 10V between every point in the diagram. But shouldn't there be a difference in voltage value between points 1 and 2 and points 3 and 4? There's a resistor between points 3 and 4.

My thinking is that if V=IR and there's a resistor between 3 and 4, it should have a different voltage than between points 1 and 2, which doesn't have a resistor between it.

Please explain why I am wrong...

It refers to any points 'before' and 'after' the resistor.
Examples voltage across points 1-4 or 1-6 or 2-5 or 3-6 and any other combinations are equal.
 


Voltage refers to a difference in potential energy across two points. It's essentially work done to move a charge between two points. In an ideal wire, there is nothing present to impede the charge from moving freely. I say ideal as real wires have some electrical resistance (superconducting wires do not).

Anyway, resistors and capacitors change the degree of work needed to move a charge. Resistors make it more difficult for charges to pass through. This creates a potential difference (this term is synonymous with voltage). So the potential energy before the resistor is different from the potential energy after the resistor. Take the difference between these energies and you get the voltage (V = IR).

Hope this helps.
 


goomer said:
It says that there should be 10V between every point in the diagram.

No. Read it again, it doesn't use those exact words it says..

The voltage between points 1 and 6 is 10 volts, coming straight from the battery. However, since points 5 and 4 are common to 6, and points 2 and 3 common to 1, that same 10 volts also exists between these other pairs of points:

Basically it's saying that in the sentence

"The voltage between points 1 and 6 is 10 volts"

you can:

Replace "6" with "5" or "4"

and/or

Replace "1" with "2" or "3".

No other combinations measure 10V. For example if you measure beween 2 and 3 you get zero volts.
 


Oh wow, I can't believe I missed that...thank you so much!
 
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