Potential Difference in an Electric Field

[LocationX]

a positive charge, q, moves a distance d from position a to b under an electric field

<------------E
<------------
<---a----b----
<------------
<------------
<------------

what is the change in potential?

This is more of a question of notation.

Should the change in potential be -Ed or Ed?

And does sign of the charge matter?

 

[borgwal]

The sign certainly matters: does the positive charge gain or lose potential energy?
Does it cost you energy to move the charge from a to b?

 

[LocationX]

The sign certainly matters: does the positive charge gain or lose potential energy?
Does it cost you energy to move the charge from a to b?

it gains potential energy

it costs me energy to move it

how does this relate to potential?

 

[borgwal]

The potential is defined as the potential energy of a positive unit charge.

The change in potential does not depend on where we define the potential to be zero.

if you know the things that "we all know," then you know what to do now.