A piece of ductile metal is in the form of a cylinder of diameter 1 cm and length 11 cm. It is drawn out into a wire of diameter 1 mm. What will be the length of the wire so obtained?
It is given in the question that,
Diameter of the wire = 1cm
Hence,
Radius of the wire = 0.5 cm
Length or the height of the wire = 11 cm
Hence,
The volume of the wire = 
= 
= 8.643 cm3
Now,
We know that,
The volumes of both the cylinders would be the same.
And,
Diameter of the new wire = 1mm = 0.1 cm
Radius = 0.05cm
Therefore the new length of the wire would be = 
= 
= 1100.02 cm
= 11 m
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