Understanding electricity in terms of electrons
Physics and electronics discussion, revision, exam and homework help.
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Understanding electricity in terms of electrons
I'm trying to understand electricity in terms of electrons and this is what I have managed to piece together. Is this correct?
1) Magnets move electrons giving them kinetic energy by a power plant/generator.
2) Electrons repel each other and as they are forced into a wire they push each other down it because of this.
3) This kinetic energy is used by appliances that use electricity and is converted to other forms, such a heat in a heater, or light and heat in a lightbulb.
4) The electrons which have now lost their kinetic energy are returned to the power plant through the neutral wire, the electron is not consumed, only their kinetic energy is.
Current: The number of electrons
Voltage: I see this described as the force with which electrons are pushed. They are pushing each other so more electrons = more force = more voltage? So voltage is a number calculated using the current, conductivity and resistance of the medium the electrons are passing through?
Does anything measurable change when the electrons kinetic energy is changed, such as current, voltage, charge? -
Re: Understanding electricity in terms of electrons
I have read your post and some aspects are correct but I will post my understanding which hopefully will help.
- In a circuit an electric field exists in the wires that is a result of the battery/generator providing one end of the wire with a positive charge and the other end with a negative charge.
-The electrons in the circuit move in this electric field which is the current.
-Electrons being negatively charged move towards the positive terminal of the battery, once they get there the battery increases their potential energy such that the electron is forced to the negative side of the battery where it then follows the electric field again around the circuit to the positive side and so on.
It is sometimes useful to think of a circuit much like a water fountain, the water (electrons) start in a pool at the bottom of the fountain, the pump (battery) then does work on the water to raise it to a greater height and in doing so gives the water greater gravitational potential energy. The water then falls down to the pool thus losing its potential energy and once again going through the cycle. From this I hope you see also that it is the potential energy that is key here not necessarily the kinetic energy, since in the fountain example the pump gives the water potential energy by raising it and similarly a battery gives electrons potential energy also.
I hope this is of some help, let me know if there is anything you would like explaining further.