When a piece of aluminium wire of finite length is drawn through a series of dies to reduce its diameter to half its original value, its resistance will become ........ times
A$2$
B$4$
C$8$
D$16$
AIIMS 1997, Medium
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D$16$
d (d) In stretching of wire $R \propto \frac{1}{{{r^4}}}$
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