Chapter 3, Problem 3.1P

To determine

Find the area ratio of the Shelby tube.

Answer to Problem 3.1P

The area ratio of the tube is $\underset{\_}{9.3\%}$.

Explanation of Solution

Given information:

The outside diameter $\left(D_o\right)$ of the Shelby tube is 3.0 in..

The wall thickness $\left(t\right)$ of the Shelby tube is 0.065 in..

Calculation:

Find the inside diameter $\left(D_i\right)$ of the Shelby tube using the Equation.

$\begin{array}{c}{D}_i=D_o-2t\\ =3-2\left(0.065\right)\\ =2.870\text{in}\text{.}\end{array}$

Calculate the area ratio $A_R\left(\%\right)$ using the Equation.

$\begin{array}{c}{A}_R\left(\%\right)=\frac{D_o^2-D_i^2}{D_i^2}\times 100\\ =\frac{{3.0}^2-{2.870}^2}{{2.870}^2}\times 100\\ =9.26\%\\ \approx 9.3\%\end{array}$

Therefore, the area ratio of the tube is $\underset{\_}{9.3\%}$.