# What does voltage really do?

I know there are many videos (many of which I have watched) and many posts (many of which I have read) about voltage, but I feel like a few points are left out that should be explained.

1. What is voltage really doing? Is it making the current move faster by using more energy (measured in joules) to move one coulomb, so is it just making current faster, which is where the pressure analogy comes from?

2. What is electrical potential, and how does it tie in with voltage?

3. Do voltage dividers limit current? And if so, how do you find out how much current is per volt?

4. What happens when voltage is increased, does more current flow?

I bet that I am misunderstanding something so if you could also explain that, it would be greatly appreciated.

This is the last question I’m going to ask for a really long time, so I hop it sends voltage home for me...

• Voltage and electrical potential are the same thing. Voltage makes charged particles try to move. Whether they CAN move or not, and how many move, depends on the property of the material where the voltage exists. In general, increasing voltage tends to make charged particles move faster. The electron is one type of charged particle, and when we look at current in a wire, for example, we are looking at electron flow. Current is how many charges pass a certain point per second. If the particles are moving faster, then that means current is higher. – mkeith Apr 21 at 22:44
• Get a 9 volt battery and a 6 volt battery, plus a red led and a 1Kohm resistor. Play with them. – analogsystemsrf Apr 22 at 3:06

As has been explained multiple times in the answers and comments to your previous questions you are confusing a physical property (energy) with the units of measure (joules). "... making the current move faster by using more joules ..." should read "... using more energy".

1. What is voltage really doing? Is it making the current move faster ..., so is it just making current faster ...

Raising the voltage will, in a resistor circuit, increase the current. Current is the flow of charge so, for a given conductor cross-section, increasing the current must increase the charge velocity. The current, however, moves simultaneously all around the circuit the same way a bicycle chain moves all links in the circuit simultaneously.

1. What is electrical potential, and how does it tie in with voltage?

As explained in my previous answer, "Voltage electric potential difference, electric pressure or electric tension is the difference in electric potential between two points." Voltage is electrical potential.

1. Do voltage dividers limit current?

Voltage dividers are usually made of resistors. Resistors limit current.

And if so, how do you find out how much current is per volt?

Use Ohm's Law. $$\ I = \frac {V}{R} \$$.

1. What happens when voltage is increased, does more current flow?

Use Ohm's Law. $$\ I = \frac {V}{R} \$$.

1) Why does the current only increase in a circuit with resistance?

I mentioned resistance as an example because they are linear. Other devices don't behave in a linear fashion; LEDs, transistorised circuits, constant current circuits, etc.

2) How does having more charges (electrons in this case -> amps) increase the velocity of the charges, and why would velocity increase the amount of charges electrons in a certain space rather than just speeding up the electrons?

To increase the amount of water going down a channel (the current) you have to speed it up or make the channel wider so that it goes at the same speed. To get more current through a point in a circuit you increase the current density (and therefore the speed of the charges) or you increase the conductor width and maintain the same density (current per unit area - measured in A/m2).

• Oh! Okay, thank you so much I know I was really having a hard time understanding last time, and that was because I didn’t know these things. So just to clarify, voltage does increase current by using more energy to make each amp flow, which makes the velocity of the electrons faster which increases the amount of electrons per specific point which is measured in amps and the amps increase because of the voltage doing that speeding up? Thanks! – BeastCoder2 Apr 21 at 22:44
• Think a bit more: "... voltage does increase current by using more energy to make each amp flow ..." No each amp will require the same energy. It will use more energy to make more amps flow."... which makes the velocity of the electrons faster which increases the amount of electrons per specific point which is measured in amps and the amps increase because of the voltage doing that speeding up?" That's pretty much right but think of "charges" rather than just electrons because positive charges move in certain situations – Transistor Apr 21 at 23:06
• Okay.. I am sorry, I have thought about it now, and have came up with two question, ONLY two questions, I won’t bother you after this. 1) Why does the current only increase in a circuit with resistance? 2) How does having more charges (electrons in this case -> amps) increase the velocity of the charges, and why would velocity increase the amount of charges electrons in a certain space rather than just speeding up the electrons? I’m sorry for taking time out of your day. – BeastCoder2 Apr 21 at 23:11
• See the update. – Transistor Apr 22 at 8:14

This image explain pretty neatly whats is happening without much technical terms

Voltage is analogous to water pressure, current is analogous to water flow. A high voltage (pressure) wants to find a path to lower voltage (pressure). If it finds one, current will flow. How much current is dependent on the resistance, per ohms law.

Electric potential is the same as voltage.

Resistance limits current. Using two resistors will create a ratio of voltages. The current is dependent on the sum of the resistors.

• 'Using two resistors in series will create...' – Chu Apr 21 at 23:48