A copper of fixed volume v is drawn to wire of length l. When the wire is subjected to a constant force f, the extension produced in the wire is delta l. What is the relationship between the force applied and the extension produced?
1) The force applied is directly proportional to the extension produced
2) The force applied is inversely proportional to the extension produced
3) The force applied is equal to the extension produced
4) The force applied has no effect on the extension produced