Biomedical Engineering Reference
In-Depth Information
X(cm)
counts per minute
1.0
380
2.0
374
2.5
379
2.6
381
2.7
375
2.8
365
2.9
308
3.0
243
3.1
181
3.2
98
3.3
10
3.4
0
Fig. 7.9
Count rate from a collimated, monoenergetic alpha-particle beam (Problem 16).
(b)
How many of these ionizations would be produced by
secondary electrons?
16.
Figure 7.9 shows an experimental arrangement in which the
count rate from a collimated, monoenergetic alpha-particle
beam is measured at different separations
x
in air. From the
given data, determine
(a)
the mean range,
(b)
the extrapolated range.
7.10
Answers
1.
∼
10
-4
0.69
13.
∼2.7
16.
7.
1.8
×
3.
5.0 MeV
4.
330 MeV cm
-1
(a)
3.1 cm
6.
34 MeV cm
2
g
-1
(b)
3.3 cm
