Electric Forces and Electric Fields

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Chapter 18

• Electric Forces and Electric Fields

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18.7 Electric Field Lines
Left figure Electric field vectors of charge q
point radially outward and
decrease in magnitude with radius r.
Right Figure Electric field lines for this charge
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18.7 Electric Field Lines
Electric field lines are always directed away
from positive charges and toward negative
charges.
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18.7 Electric Field Lines
Electric field lines always begin on a positive
charge and end on a negative charge and do not
stop in midspace.
Electric field lines between positively and
negatively charged slabs of material held close
to one another.
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18.7 Electric Field Lines
The number of lines leaving a positive charge or
entering a negative charge is proportional to
the magnitude of the charge.
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18.7 Electric Field Lines
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18.7 Electric Field Lines
There are three things wrong with part (a) of
the drawing. What are they?
(b) Shows a correctly drawn set of electric field
lines for these charges