Various lightweight composite materials are being tested for possible use as structural columns in a space station. Small samples of each composite (cross-sectional area = A_sample in units of in²) are stretched elastically in a large press until the sample length has increased from 2 cm to 2.03 cm, and the stretching force applied by the press (F_press in lbƒ) is recorded at that point. The National Aeronautics and Space Administration (NASA) wants to know how much force (F_column in lbƒ) would be required to elastically stretch a structural column (crosssectional area = Acolumn in units of in²) by 1.2%.
a. Derive a relationship for calculating F_column from F_press, A_sample, A_column, and the given magnitudes of elastic stretching.
b. The Excel spreadsheet shown below has been constructed to perform the calculation in part (a) using data entered into the other cells as shown. Complete the spreadsheet by writing the function exactly as it would be entered into cell B8 to provide the value of F_column for any values entered into cells B3, B4, and B6.

Transcribed Image Text:

A 1 Prediction of Force on Structural Column 2 3 Force on Sample to stretch 2->2.03 cm (lbf): 4 Cross-sectional Area of Sample (in^2): 5 6 Cross-sectional Area of Structural Column (in^2): 7 8 Force on Column for 1.2% Stretch 9 B 30,000 0.196 40 function you enter