Homework Help: Number of Wires & Cross-Sectional Area

1. Sep 20, 2011

BranTkC

Hi there, I'm a student in high school.
I'm quite new to the forum. Please forgive my mistakes.

The problem statement, all variables and given/known data
My question is related to electricity, more specifically the factors affecting resistance in a wire. I know that resistance is inversely proportional to the cross-sectional area of the wire.

Does the number of wires represent the cross-sectional area of the wire?

Relevant equations
The circuit diagram is in the attachment.
I came across an experiment which describes that by changing the number of wires (ie. changing the number of eureka wires), we actually change its cross-sectional area.

The attempt at a solution
However, doesn't adding the number of wires make it become a parallel circuit?￼

Attached Files:

• Resistance.jpg
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2. Sep 20, 2011

davo789

By adding more wires between points x and y, you are increasing the cross section of wire between these points. Between x and y, these wires are in parallel (so there is less current flowing through each wire. Using V=IR where V = const you can see that R reduces).

3. Oct 2, 2011

BranTkC

Alright. Thanks!!