Need a good conceptual explanation PLEASE

[cdistel]

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Can someone please conceptually explain the difference between Current and Voltage (or potential). I know the equation V=IR but want to grasp the material,I have heard of current as thinking of electrons like water flowing through a stream (the wire being the stream and electrons being water), but I can't wrap my mind around voltage. Thanks for the help best of luck with your studies!
-Chris

 

[randomb]

Current and voltage are completely different. Current is simply a measure of how many electron goes through a given wire multiplied by the charge of an electron (so it's just the amount of charge going through something).

Voltage is electric potential. You can have electrical potential energy just like you can have gravitational potential energy. Voltage measures how much energy you'd get when an electron or any charged object moves x meters.

 

[DougTPR]

I have heard of current as thinking of electrons like water flowing through a stream (the wire being the stream and electrons being water), but I can't wrap my mind around voltage.

Stick with that for current.

Voltage can be thought of as the height drop from the beginning of the stream and the end of the stream (i.e., from the headwaters to the ocean).

You can extend this to encompass the parts of a circuit as well. Resistors as e- dams for example.

 

[cdistel]

Hey Douglas thanks for the explanation definitely makes some sense. It is a little harder to conceptualize than gravitational potential energy but makes more sense now thanks!

 

[Rabolisk]

Every point on a circuit has a certain potential. The difference in potential between two points, or voltage, makes charge flow (i.e. current). This is analogous to the fact that the difference in gravitational potential between the ground and the air causes the object to drop to the ground. You probably think of gravity in terms of force rather than energy (potential), but in circuits, it is easiest to think in terms of energy.

 

[venacontracta]

Electricity is the flow of electrons. Electrons "want to" move in an energetically favorable way - in other words, from a place where they have higher potential energy to a place where they have lower potential energy.

An analogous situation would be marbles falling off a cliff. The marbles are electrons. In this situation, we still have potential energy, but it takes the form of gravitational potential energy. Marbles will only fall down the cliff (not back up the cliff) because only falling down the cliff will decrease their potential energy.

Current is the number of marbles which fall off of the cliff per second.

Voltage is the difference in potential energy between the top of the cliff and the bottom of the cliff.

I personally prefer this analogy for understanding current and voltage rather than the more common water one. I think using something which has easy-to-visualize discrete particles rather than something which "flows" helps understand what is actually going on at the smallest level. The only big problem is that this way of explaining things breaks down when it comes to resistance.

 

[DougTPR]

Voltage is the difference in potential energy between the top of the cliff and the bottom of the cliff.

I like this one 🙂

Although, to be totally accurate, voltage would be the difference in potential between the top and bottom of the cliff. Electrical potential energy is the corresponding concept to gravitational potential energy. Although I see the value in your usage since we don't often use or discuss gravitational potential all that much.