Question

The radius of a metal sphere is 3 cm. The sphere is melted and made into a long wire of uniform circular cross-section, whose length is 36 cm. To calculate the radius of wire, complete the following activity.

Radius of the sphere = `square`

Length of the wire = `square`

Let the radius of the wire by r cm.

Now, Volume of the wire = Volume of the `square`

`square` = `square`

r² × `square` = `square` × `square`

r² × `square` = `square`

r = `square`

Hence, the radius of the wire is `square` cm.

Answer 1

Radius of the sphere = 3 cm

Length of the wire = 36 cm

Let the radius of the wire by r cm.

Now, Volume of the wire = Volume of the sphere

πr²h = `bb(4/3)` πR³

r² × 36 = `bb(4/3)` × 3³

r² × 36 = 36

r = 1

Hence, the radius of the wire is 1 cm.