Charge different entering and leaving a resistor

[Seung Tai Kang]

Homework Statement

Is a charge different upon its exit versus its entry into the lightbulb?

Homework Equations

PE = Vq

The Attempt at a Solution

Well, the answer is that the charge stays the same. Based on the equation above, since energy certainly gets reduced V must drop but I don't understand how charge stays the same. And the answer says it is "at a location that is lower in potential." Can someone help me grasp this idea?

 

[phyzguy]

Think of water flowing through a pipe. The same amount of water enters the upstream end of the pipe as leaves the downstream end. This has to be true, because there is nowhere in the pipe for water to be stored. The water flow is analogous to current. However, the water pressure at the output end is lower than at the input end because some pressure is dropped due to the friction of the water with the pipe walls. The pressure is what pushes the water along and is analogous to voltage or potential.

 

[scottdave]

Voltage, Potential, and Electromotive Force are all terms which are used to describe the same thing.
http://hyperphysics.phy-astr.gsu.edu/hbase/electric/elevol.html#c1

Note that Potential is different than Potential Energy.

 

[CWatters]

A current is a flow of electrons. Individual Electrons have constant/fixed charge.