A ring torus is made by joining the circular ends of 1 meter long thin and elastic tube. If the radius of the cross section is 3.18 cm, how do you prove that the volume of the torus is $19961$ cc?

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Answer 1 · 2016-09-26T09:36:23

See explanation

If a is the central radius to the axis of the torus and b is the radius of

the cross section, the volume is

$2pi^2ab^2$ cubic units.

Here a = 1 meter = 100 cm and b = 3.18 cm. So, the volume is

$2pi^2(100)(3.18)^2$ cc

$=19961$ cc, nearly.

Had the cross sectional radius been given as

$b=1/(sqrt 2pi)$ meter

$22.5079079.....$ cm, the volume would be exactly

1 cubic meter.

A ring torus is made by joining the circular ends of 1 meter long thin and elastic tube. If the radius of the cross section is 3.18 cm, how do you prove that the volume of the torus is 1996119961 cc?