A metallic sphere of radius 4.2 cm is melted and recast into the shape of a cylinder of radius 6 cm. Find the height of the cylinder.
Given:
A metallic sphere of radius 4.2 cm is melted and recast into the shape of a cylinder of radius 6 cm.
To do:
We have to find the height of the cylinder.
Solution:
Radius of the metallic sphere$r_1=4.2\ cm$.
Radius of the cylinder$r_2=6\ cm$
Let the height of the cylinder be h.
The cylinder fromed by recasting the sphere will be same in volume.
Therefore,
Volume of sphere $=$ Volume of cylinder
$\frac{4}{3} \pi (r_1)^3= \pi (r_2)^2h$
$\frac{4}{3}\times\frac{22}{7}(4.2)^3=\frac{22}{7}\times(6)^2h$
$h=\frac{4\times4.2\times4.2\times4.2}{3\times6\times6}$
$h=1.4\times1.4\times1.4$
$h=2.74\ cm$
The height of the cylinder formed is 2.74 cm.
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