Question concerning Electric Field

[momomo_mo]

I want to ask things about chapter "Electric Fields"
I am stucked in these words " Potential, Electric Fields, equipotential ..."

1.Why do we call potentail difference - Voltage?

2.Why do we call 2 objects have the same potentail if they are in contact with each other?

3.I am frustrated with the definition of potential -Work done per unit charge in bringing from infinity to the point r? How can it apply to the electrons in the circuit?

Thanks

 

[thiotimoline]

I want to ask things about chapter "Electric Fields"
I am stucked in these words " Potential, Electric Fields, equipotential ..."

1.Why do we call potentail difference - Voltage?

2.Why do we call 2 objects have the same potentail if they are in contact with each other?

3.I am frustrated with the definition of potential -Work done per unit charge in bringing from infinity to the point r? How can it apply to the electrons in the circuit?

Thanks

Potential difference is analogous to the difference in terms of current. A difference means there is a flow, and is called voltage.

 

[Hootenanny]

Just further to what thiotimoline said;

1.Why do we call potentail difference - Voltage?

Voltage was so named after the inventor of the voltaic pile (a rudimentary battery), A. Volta - I forget his first name. The volt is not a [SI] base unit but rather a derived unit. The base unit of potential difference is defined as the energy transferred per unit of charge, J.C^-1. Equally, one volt can also be described as the potential difference when a current of one ampere dissipates one watt of power in a conductor and so can also have the base unit m².kg.s^-3.A^-1.

2.Why do we call 2 objects have the same potentail if they are in contact with each other?

Perhaps you can answer this one yourself, what creates a potential [difference]?

3.I am frustrated with the definition of potential -Work done per unit charge in bringing from infinity to the point r? How can it apply to the electrons in the circuit?

Quite simply in any circuit there is an electric static field which requires work to be done to move a charge, remember a definition of voltage - work done per unit charge?. Perhaps http://en.wikipedia.org/wiki/Electric_potential" from wikipeda on electric potential would be helpful.