 NEWTON, Ask A Scientist! Name: Dan F. Status: student Age: 13
Location: N/A Country: N/A Date: 5/15/2003  Electric Field
Strength (E = V/d or -V/d ?). Most website show that E = V/d.
For example, one site says, "If you want to move the positive
test charge from a position of low to high potential energy, you
must do work on the object against the electric field. You would
calculate it using...  W = Fd  Remember from before that E = F/q
F =qE  So the change in potential energy of the charged object
is W = qEd "  Also, it shows "V = Ed for electric potential in a
uniform field."  Here is my inquiry:  According to the A.P.
Physics book from Princeton Review, potential difference is
defined in terms of an "external force" doing work "against" the
Electric Field (W_ext) -not in terms of the work done BY the
electric field (W_e = work done BY field).  Potential difference
= V = W_ext/q.... and, in fact, A.P. Physics explicitly says
that V = W_e/q (Note the negative sign before the W_e.)  Now,
the work done BY the