Question

The length of a wire is doubled. By what factor does the resistance change 1 point

Answer 1

Let the resistance of the wire be R. The length of the wire reduces by 1/2, and the area increases by 2 times. Thus, the resistance of the wire reduced by 1/4 times.

Answer 2

It depends if the more of conductor is added or if the original wire is stretched. If more wire is added, surface area doesn’t decrease but if wire is stretched the area would reduce. I will try and explain both situations.