Question

13. A cylindrical wire is of length 18 cm and diameter
2 cm. It is pulled into a wire of diameter 2 mm. Find
the length of the wire.​

Answer 1

Answer:

R=1cm

H=18cm

r=1 mm= o.1 cm

volume of 1st wire = volume of 2 ND wire

πR^2H =πr^h

1x1x18= 0.2x0.2 xh

h= 450 cm= 4.5 m

Answer 2

Vol. of cu sphere = Vol. of cu wire.

⇒

3

4

πr

3

=πr

1

2

l

⇒

3

4

π×9

3

=π2

2

l×(10

−1

)

2

⇒

l=243m