Question

a 3600 cm long copper wire of 0.1 cm radius was melted and shaped into a sphere.find a]volume of wire b]radius of sphere c]volume of sphere [take$\pi$ =3.14]

Answer 1

According to the question, the wire is in the form of a cylinder,

a)Thus volume of cylinder = πr²h
= 3.14 x 0.1² x 3600
= 113.04cm³

b) The volume of sphere will be equal to that of the wire as the sphere is molded from it 
So, 4/3πr³ = 226.28
= 4/3 x 3.14 x r³ = 226.28
= r³ = 113.04x 3/(4 x 3.14)
= r³ = 54
= r = √54 = 3.77cm

c) We know that volume of wire and sphere are equal. Thus volume of sphere = 226.08cm³

Hope it helps !!

Answer 2

the radius of sphere is 3 cm and v of sphere is 113.04 and v of wire=113.04
NOW,
                     wire is cylindrical
                     v=pie r sq. h=>3.14*1/10*/10*3600=113.04
                     v of the cylinder(wire) is 113.04
YOU KNOW V. OF WIRE=V. OF SPHERE
and
                     v of the sphere will be 113.04
so,,, v of sphere=2/3 pie r cube
                     pie r cube=113.04*3/2
                     r cube=113.04*3/2/3.14
                     r cube=54.00
                     r=cube root of 54=>3.77
<>                >r of sphere=3.77 cm