Why is potential difference the same across each branch in parallel?

[aidandv]

As the title says, i am struggling to understand how if the cell is only supplying 3V how 2 lamps in parallel both receive 3 volts (totalling 6)

I currently study a level physics and never really questioned how this works and just accepted it as the truth.

Can someone explain with a helpful analogy?
thank you

 

[kuruman]

In the standard circuit diagram, each lamp is connected to the battery with a straight lines and there are no other circuit elements between the lamps the battery terminals. Straight lines are equipotentials. Thus the potential has the same value $V_1$ on one side of both lamps and the same value $V_2$ on the other side of both lamps. That means that the lamps are in parallel.

 

[scottdave]

The analogies presented in this video may help you understand.

Sorry I had a bad link when initially posting.

 

[aidandv]

The analogies presented in this video may help you understand.

Sorry I had a bad link when initially posting.

Hi is there a specific timestamp for my question?

 

[aidandv]

In the standard circuit diagram, each lamp is connected to the battery with a straight lines and there are no other circuit elements between the lamps the battery terminals. Straight lines are equipotentials. Thus the potential has the same value $V_1$ on one side of both lamps and the same value $V_2$ on the other side of both lamps. That means that the lamps are in parallel.

So what youre saying is in parallel both components have the same potential for charge carriers to do work so theyre the same?

 

[kuruman]

I am saying that two conductors in parallel have the same potential difference across their ends.

 

[aidandv]

I am saying that two conductors in parallel have the same potential difference across their ends.

i dont quite understand what this means

 

[Lnewqban]

i dont quite understand what this means

All the consumer elements in a car "feel" the 12 volts delivered by the car battery.
They are all in parallel to each other and having one consuming electricity does not affect what the other one is receiving.

 

[scottdave]

Hi is there a specific timestamp for my question?

So this addresses the concept of electric potential, rather than parallel circuits in particular. I think many students get confused on electric potential. There was another video that I was looking for concerning series and parallel circuits, but I haven't located it yet.

 

[kuruman]

As the title says, i am struggling to understand how if the cell is only supplying 3V how 2 lamps in parallel both receive 3 volts (totalling 6)

I think I see now what you mean. Here is the fluid analogy for a circuit. The potential difference across two conductors is analogous to the pressure difference across the constrictions. When you have two constrictions in parallel (bottom drawing taken from the link) the pressure difference between the ends is not additive. Likewise, if the potential difference (think of it as the pressure driving the flow of charge carriers) is not additive. In parallel conductors the currents are additive not the potential differences.

 

[aidandv]

I must be really dumb or smth bc I’m still not understanding. It’s ok tho dont worry about it

 

[Lnewqban]

You may

I must be really dumb or smth bc I’m still not understanding. It’s ok tho dont worry about it

You may be confusing voltage with current.