(3) The decay rate also may be calculated from the plotted slope by measuring each axis and
y
using the formula n =
.
x
(a) To do this, measure the distance from the point where the "best fit" line crosses the
y-axis directly down to the bottom of the log-log cycles. Record this measurement as the y . Measure
from the point where the best fit line crosses the x-axis directly to the left edge of the log-log-cycles.
Record this measurement as the x . See the example measurements for locations A and B in Figure 4-5.
100
90
80
LOCATION C
70
60
50
40
A
128
LOCATION A
mm
y
C1
20
39mm
X
C
10
35mm
9
B
8
89mm
7
LOCATION B
6
5
4
A 107mm
B 87mm2.0
0.3
0.5
1.0
4.0
6.0
7.0
x axis
Time after burst (H + ___ hours)
Figure 4-5. Decay Rate Determination Measurement of Slope
CM2306
4-10
Previous Page
