Question

W2. If the number of counts per unit time that remains after a beam of particles passes through a thickness x of a material is given by (21.2) then one can easily see that dividing by I, and taking the natural logarithm of both sides, one obtains (21.4) Plot In(I/Io) versus x in Excel. Introduce a linear Trendline to curve-fit the data, and do not forget to select "show equation on graph". The slope of the line will give you -u. Make the graph of the data reasonably large to clearly show the deviations of the Trendline points from the actual data. The value of u for Pb from The Handbook of Physics and Chemistry is 1.15 cm (note that this value must be converted in order to conduct any comparison, since, in our experiment, we are measuring thicknesses in millimeters). Compare your result obtained using Excel to the accepted value. Calculate the percentage difference. Important: Do not include the zero-thickness point when plotting the data and the Trendline in Excel. P2 (Background Measurements): 2.禸 3. 10 4. 15 Average: 12.4 P3 In (I/ Io) ounts (with I(Counts minus Thickness (mm) 0.00 0.79 Background) Background) 6 47 451 In (lol lo) (do not plot) To- 534.6 5 2 36 5. 6 3.18 6.35 9.53 379 378 2L0 P4 Counts N (Counts minus Background) Counts . 1539 2. 1602 3. t96 4. 1506 5, 1511 N (Counts minus Background) 1506. 6. 19i 576.0 15SA.6 5H56 443 7. 1445 8. 636 1623. с 1558 6 1606k

Answer 1

Io Thickness(mm 0.79 1.59 3.18 6.35 9.53 0.198 0.0498 0.379 0.726 0.995 In(l/lo) vs thickness 2 4 -0.2 Series! Linear (Series1) y--01 042x-00229 RA2 0.9489 -0.6 0.8 thickness(mm) 1.2

The slope of the line, m -0.1042 mm1 The absorption coefficient, μ-m-0.1042mm-ー1.042cm-1 1.15一1.042 × 100 = 9.3913 The percentage error= 1.15