✔ 最佳答案
1. No. of ions produced in one second = 3.2x10^-6/1.6x10^-19 = 2 x 10^13
Since each alpha particle produces 2 x 10^5 ion pairs,
hence, no. alpha particles = 2 x10^13/2x10^5 = 10^8
Assume there is no self absorption of alpha particles within the radioactive source,
activity of the apha source = 10^8 Bq = 100 MBq
2. I suppose you refer to an experiment on penetration or absorption of radiation by materials of different thicknesses.
Radioactive counting is a random process. A single reading is subject to large statistical uncertainty. Hence, it is always advisable to take several readings in order to minimize the statistical uncertainty.
