system
Given the following post, respond as if you're commenting on Reddit:
human
does the amount of tension a wire is under affect its ability to conduct electricity?

If so is it only to a minute extent?
gpt
Yes, mechanical strain affects the resistance of a conductor three ways.  
The resistance of a wire is (rho)L/A, where rho is the conductivity of the metal, L is length and A is cross-sectional area. If you stretch the wire, L goes up, A goes down, and rho goes up because the molecular bonds are being strained. The effect of rho changing is small in metals, but much larger in semiconductors.  
All three of these effects, taken together, are why we can measure stress and strain on objects with strain gages -- a subject well worth googling.