Question
Mon December 26, 2011 By: Aman Singhal

# Why does the balancing length of potentiometer wire remains same when there is change in area of cross section of the wire? Resistance is inversely proportional to area of cross section,in this case how can it be independent of area? Plz Explain.

Expert Reply
Tue December 27, 2011
for potentiometer, V/l = constant=?I/A     ( comes from V=IR=I?l/A)
if the area of cross section is same through  out  then it does not matter  whether the area is more or less.
as ?, l, A  are constant  for any part of the wire.
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