Given,
Radius of the sphere = 9/2 cm
So, its volume = 4/3 πr3 = 4/3 π(9/2)3
And, the radius of the wire = 2 mm = 0.2 cm
Let the length of the wire = h cm
So, the volume of wire = πr2h = π(0.2)2h
Then, according to the question we have
Volume of wire = Volume of sphere
π(0.2)2h = 4/3 π(9/2)3
h = 4 x 729/ (3 x 8 x 0.01) = 12150 cm
Therefore, the length of the wire = 12150 cm