Posted by Melissa on Wednesday, February 15, 2012 at 1:07am.
A wire of length L and crosssectional area A has resistance R. What will be the resistance R_stretched of the wire if it is stretched to twice its original length? Assume that the density and resistivity of the material do not change when the wire is stretched.
Express your answer in terms of the wire's original resistance R.

Physics!! Help!!!!!  drwls, Wednesday, February 15, 2012 at 1:15am
The product L*A remains constant after stretching. If L doubles, A decreases by 1/2
Resistance is proportional to L/A.
R2/R1 = L2/L1 *A1/A2 = 4
R1 is the original resistance and R2 is the final resistance. 
Physics!! Help!!!!!  If the diamèter of the wire is doubled and its length is halved then its young's modulus, Sunday, May 4, 2014 at 12:21am
A)becomes double B)remains same C)becomes half C)becomes square

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Remain same

Physics!! Help!!!!!  MANIRAGUHA Eric, Sunday, September 4, 2016 at 2:56am
Consider a cSi solar cell whose fingers have a resistance R=0.1 Ohm. What would be the finger's resistance (in Ohm) if the finger's width is doubled and the finger's height is one third of its initial value?