Area of a U shaped tube

[Liquidmetal]

I still need help on figuring out the outside surface area of a u shaped tube.

I the diameter of the tube is 2", and the height is 10" and the od of the U is 10" how do you figure the length of the tube. (formula)

Once I have the length of the tube I can use the cylinder area formula

Please help

 

[BigGlenntheHeavy]

Is this the cross section of the tube? If it is, assume the red area is a water tube and the white area is insulation to keep the water tube from freezing in the winter. Now, for a 10 inch tube, we have:

\(\displaystyle Outward \ lateral \ surface \ area \ of \ insulation \ = \ 2\pi r h \ = \ 2\pi(5)(10) \ = \ 100\pi \ sq. \ in.\)

\(\displaystyle and \ Inward \ lateral \ surface \ area \ of \ water \ tube \ = \ 2\pi r h \ = \ 2\pi(1)(10) \ = \ 20\pi \ sq. \ in.\)

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