Question

a piece of wire is redrawn without change in volume so that its radius is halved.compre the new resistance with the original resistance

Answer 1

 The new Radius is half, which makes the new cross sectional area {pi*radius²} equals pi*(R/2)², which becomes (pi/4)*R². This is 1/4 of the original area {not one half}, and the length is mulitplied by 4 to maintain same volume. 

So we have 4 divided by (1/4) equals 16. The new resistance is 16 times the original resistance.

Please mark it as brainiest answer .........