Question #56177

1 Answer
Nov 10, 2016

Answer:

See proof below

Explanation:

The resistance of the first wire is #R=rhol/a#
where #rho=# resistivity for this material
#l=#length
#a=#area #=pir^2# where r is the radius

New length #=l/2#

New radius #=r/2#

The second wire #R_1=rho*(l/2)/(pir^2/4)#

#=(4rhol)/(2pir^2)=(2rhol)/(a)=2R#

So the new resistance is twice the other resistance