2.2 cubic decimeter of metal is to be drawn into a cylindrical wire of diameter 0.05 cm.Find the length of wire.
Let the length of the wire be h cm.
Volume of metal = 2.2 dm3 = 2.2 × (10 cm)3 = 2.2 × 100 cm3 = 2200 cm3 ( 1 dm = 10 cm)
Let r be the radius of the cylinder.
Given, 2r = 0.05 cm
Volume of metal in the wire = 2200 cm3
∴ πr2h = 2200 cm3
Thus, the length of wire is 112000 dm.