Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

High voltage low current

  1. Mar 1, 2012 #1
    How do you get a high voltage, low current? This is where I am getting confused. I was under the impression, that the more charge you have on an object the bigger the electric field, being produced, so the bigger voltage. As a charge is carried by either and electron or proton, the more electrons on a charge object the more voltage there is the more current will flow due to a huge amount of electrons need to be discharged. Or is that the electrons that are bound to a material gain the charge thus creating the electric field, and depending on the amount of free electrons available would dictate how much current would flow so to speak, as current is a specific flow of electrons which would be repulsed by the negative charge on the object.
     
  2. jcsd
  3. Mar 1, 2012 #2
    just think of Ohm's law that is V=IR. If there is large voltage and large resistance then you will get minor current. For example. Voltage=1000V resistance =10,000 ohm then current will 0.1 A. But if resistance is of 10 ohms then 100A current flow(I take bigger digits to make large difference). If you want to know it more deeply look for derivation of Ohm's law.
    I have tried to explain. have a look on it.
    If there is a large potential difference then there will be large electric field(length dl should not too lare) dV= - E.dl, but large electric field doesn't mean huge current. it is ease of electron with which they wants to come out of their outermost shell. If It is too tough to pull them out then that material will have larger resistance and even after applying large potential difference you will get minor current. sometimes conduction is also through holes but this time electrons are enough.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook