Given:
44 cu. cm of wire is drawn into a wire of diameter 2 mm.
To find:
The length of the wire.
Solution:
We know that,
1 cm = 10 mm
1 cu. cm = 1000 cu. mm
We have, a wire of cylindrical shape.
Volume of the wire = 44 cu. cm
= 44000 cu. mm
Radius of the wire = 2 mm
Volume of a cylinder is:
![V=\pi r^2h](https://tex.z-dn.net/?f=V%3D%5Cpi%20r%5E2h)
Where, r is the radius and h is the height.
Putting V=44000,
and r=2, we get
![44000=\dfrac{22}{7}\times 2^2\times h](https://tex.z-dn.net/?f=44000%3D%5Cdfrac%7B22%7D%7B7%7D%5Ctimes%202%5E2%5Ctimes%20h)
![44000\times \dfrac{7}{22}=4h](https://tex.z-dn.net/?f=44000%5Ctimes%20%5Cdfrac%7B7%7D%7B22%7D%3D4h)
![14000=4h](https://tex.z-dn.net/?f=14000%3D4h)
Divide both sides by 4.
![\dfrac{14000}{4}=h](https://tex.z-dn.net/?f=%5Cdfrac%7B14000%7D%7B4%7D%3Dh)
![3500=h](https://tex.z-dn.net/?f=3500%3Dh)
Therefore, the length of the wire is 3500 mm or 350 cm.