Volume of a torus Calculator

Calculates the volume and surface area of a torus given the inner and outer radii.

 inner radius a outer radius b b≧a 6digit10digit14digit18digit22digit26digit30digit34digit38digit42digit46digit50digit volume V surface area S
 $\normal Torus\\(1)\ volume:\hspace{50} V={\large\frac{1}{4}}\pi^2(a+b)(b-a)^2\\(2)\ surface\ area:\hspace{10} S=\pi^2(b^2-a^2)\\$

Volume of a torus
 [1-10] /56 Disp-Num5103050100200
[1]  2018/11/27 17:14   Male / 60 years old level or over / Self-employed people / Very /
Purpose of use
Volume of o ring.
Comment/Request
Enhancement suggestion. Calculating volume of O ring sold as 13.95 inside diameter and 2.62mm thickness required use of another calculator before use of torus calculator. 15mm by 2mm O ring can be done in my head before using Torus calculator
[2]  2018/11/16 03:54   Male / 50 years old level / An engineer / Very /
Purpose of use
As a demonstration tool
Comment/Request
Since o-rings are typically specified (& sold) by inside diameter and the cross section this would be a very useful (& time saving) option
[3]  2018/10/02 06:19   Male / 30 years old level / An office worker / A public employee / Very /
Purpose of use
Checked against what I guessed would be the volume of a torus. My equation was longer, but this was the simpler version.

I guessed it was the radius of the torus, times the average of the circumferences.
Pi*[(b-a)/2]^2*[(2*Pi*b)+(2*Pi*a)/2]

Turns out I was right, and after factoring it out, I reduced it to the same equation.
Comment/Request
It's great. A note explaining that it is similar to calculating a cylinder, and that you are averaging the circumference to get the "length" would be nice.
[4]  2018/09/24 10:25   Female / Under 20 years old / High-school/ University/ Grad student / Useful /
Purpose of use
physics experiment
[5]  2018/09/22 03:58   Female / Under 20 years old / High-school/ University/ Grad student / A little /
Purpose of use
Checking a derived equation
[6]  2018/08/05 14:43   Male / 50 years old level / A teacher / A researcher / Very /
Purpose of use
calculate the volume of an inner tube to estimate buoyancy and weight carrying capacity on water
[7]  2018/07/30 16:19   Male / 60 years old level or over / A teacher / A researcher / Useful /
Purpose of use
to determine required depth of fitment for an O ring
[8]  2018/07/13 23:26   Female / 20 years old level / An engineer / Useful /
Purpose of use
calculating the volume of the elbow of a pipe
[9]  2018/05/30 08:28   Male / 40 years old level / Others / Very /
Purpose of use
Designing an anchor for a floating trampoline.
[10]  2018/05/29 07:50   Female / Under 20 years old / High-school/ University/ Grad student / Very /
Purpose of use
A project for my AP calculus class

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