Question

17. The diameter of a sphere is 42 cm. It is melted and drawn into a
cylindrical wire of diameter 2.8 cm. Find the length of the wire.
​

Answer 1

Answer:

Given

diameterofasphere=42cm

radius=

2

42

=21cm

Now,

Volumeofsphere=

3

4

πr

3

=

3

4

×

7

22

×21×21×21

=4×22×21×21

=3,8808cm

3

Volumeofsphere=volumeofcylinder

38,808=πr

2

h

⇒38808=

7

22

×14×14×h

h=

11

696

h=63

Hence,lengthofwireis63cm.