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    Is EP same as EF, or am i right in assuming the EP is based on the distance whilst EF is not?
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    (Original post by Dexter212)
    Is EP same as EF, or am i right in assuming the EP is based on the distance whilst EF is not?
    They are very different:

    1. The electric field \vec{E} tells you about the force felt by a charge A due to another charge, B. It tells you the magnitude and direction of the force that charge A will feel because of the presence of charge B, so it associates a vector with each point in space. It is thus called a "vector field" - you can think of this pictorially as an arrow with some length and direction at each point in space. Sometimes we draw these joined together as field lines. The magnitude of this vector has units newton per coulomb, which is equivalent to volt per metre.

    2. The electric potential V associated with point P tells you how much work you have to do to move a unit +ve charge from some reference point (usually infinity i.e. a point infinitely far away) to P. This is just a number, since work is given by a number (with unit joule per coulomb, which is equivalent to volt). So the electric potential for a charge B associates a single number with each point in space. Numbers are often called scalars in physics, so electric potential is a "scalar field".

    You can calculate the electric potential from the electric field by a calculation related to "work = force x distance" though in more than one dimension, you need maths beyond A level to do so.
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    (Original post by atsruser)
    They are very different:

    1. The electric field \vec{E} tells you about the force felt by a charge A due to another charge, B. It tells you the magnitude and direction of the force that charge A will feel because of the presence of charge B, so it associates a vector with each point in space. It is thus called a "vector field" - you can think of this pictorially as an arrow with some length and direction at each point in space. Sometimes we draw these joined together as field lines. The magnitude of this vector has units newton per coulomb, which is equivalent to volt per metre.

    2. The electric potential V associated with point P tells you how much work you have to do to move a unit +ve charge from some reference point (usually infinity i.e. a point infinitely far away) to P. This is just a number, since work is given by a number (with unit joule per coulomb, which is equivalent to volt). So the electric potential for a charge B associates a single number with each point in space. Numbers are often called scalars in physics, so electric potential is a "scalar field".

    You can calculate the electric potential from the electric field by a calculation related to "work = force x distance" though in more than one dimension, you need maths beyond A level to do so.
    Amazing response, Best response ever. Thank you very much.
 
 
 
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