(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

We did an experiment using resistance putty and a multimeter. We changed the radius of the putty but kept the length the same. We recorded the resistances at different radius'. I know that physics theory says that resistance is inversely proportional to cross-sectional area of wire. For example, if the radius doubles, the cross sectional area increases four times and the resistance decreases by four times.

2. Relevant equations

radius (m) resistance (Ω)

0.0015 601

0.003 270

0.0075 72.4

0.0115 50

0.015 43

3. The attempt at a solution

However my results don't follow the theory at all. the resistance decreases by closer to 2 or 3 times when the radius doubles.

I'm kind of stumped by this. Thanks for any help or pointers in the right direction :)

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# Homework Help: Inverse relationship between radius and resistance

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