Engineering 103 –UMass Boston

CW 5

(In-Class-Work 5)

1.- Import the data (metal distance and ultrasonic response) from http://www.itl.nist.gov/div898/handbook/pmd/section6/pmd631.htm into Excel (it helps to save them into a text file and then use ‘Data/Get External Data/Import text file’ with the ‘fixed width’ option). Produce a non-linear fit of the ultrasonic response Y’ as a function of the metal distance X, with model Y’=exp(-b1*X)/(b2+b3*X). When importing data, note that in that website, the ultrasonic response (Y) appears in the first column, and the metal distance (X) in the second column. Plot the data and best fit on a same plot. Then copy the plot into a Word file. Also provide b1, b2, b3, and the final ‘standard’ deviation coefficient.

2.- In the same Word file, estimate the cost to paint a computer (use flat surface approximation; $5.00/liter; 1 liter=0.001 m³;

1 mil=0.025 mm) Include sketches of your computer.

click here to submit the zipped Word file. Remember it should be named ‘cw5_yourlastname’

*Remember that this is an individual work (turn it in, as instructed, with your name and date). Home-works and class-works count 20% toward the course grade. Class-works are done in class.