Most recent answer: 03/10/2017

Q:
A wire has 100 ohm resistance and a length of 10 meter. If it is stretched in such a way that it's length increases 3 times. What will be it's new resistance?
- Taha (age 17)
Taif, K.S.A
A:

Whoever assigned this problem no doubt wants you to use simple geometry to answer it. I should point out, however, that in metallic wires defects in the metal are an important source of electrical resistance. Stretching the wire will probably introduce more defects.

Mike W.


(published on 03/10/2017)