# Theory : High voltage but low current

• A generator products electrons that it sends into wire
• The electron motion is due to the repulsive behavior between electrons

So to increase the voltage (speed of electrons?), generator have to produces more electrons or send more into wire. That will increase the speed of electrons because electrons have now more kinetic energy (V=J/C).

But in this case there are more electron so the current is automatically increase too. Indeed I=C/S, the number of electron by second.

So for a power of 100W for example, how it is possible to produce 1000V with 0.1A and conversely ?

I'm really not sure to have well understood, can you please correct my mistakes and answer my question ? Thanks!

• EDIT :

I understand that electron speed is calculated with the area of the conductor (its diameter) and the current. More the area is small and more the current is high, more the velocity increase.

I understand the comparison of the voltage with pressure but i still don't know how you can increase this electron pressure. If it's not by adding more electron into wire, what is the method ?

• Voltage (or "tension" as you called it) is not the speed of electrons. Electrons move at a very low speed through conductors - that speed is mostly dictated by the material of the conductor. See "electron drift speed." – JRE Mar 23 '18 at 12:02
• Yes i read that too, electrons are very slow, so what is the point of voltage, physically what does it do, and how does it ? Current is easier to imagine number of electron by seconds, but i really don't understand what a generator does to increase or decrease voltage and what are the consequences – foxem Mar 23 '18 at 12:11
• @Rain Voltage is equivalent to pressure in a hose pipe. You can have very low flow at very high pressure. Or very low pressure and veryhigh flow. Depends on things like the diameter or "resistance" of the pipe. – Dirk Bruere Mar 23 '18 at 12:15
• The drift velocity of electrons in a conductor, ie the current, depends on the voltage across the conductor and it’s material. – Chu Mar 23 '18 at 12:17
• @DirkBruere For me, to increase the pressure you have to increase speed of electrons, and to do that you have to produces more electron, but that's not correct. It's what i don't understand. – foxem Mar 23 '18 at 12:20