Physics-
General
Easy
Question
A 7Li target is bombarded with a proton beam current of 10-4A for 1 hour to produce. 7Be of activity 1.8 x 108 disintegrations per second. Assuming that one 7Be radioactive nucleus is produced by bombarding 1000 protons. Half life of 7Be is ………….. (approx.)
- 6.63 x 106 sec
- 7.63 x 106 sec
- 8.63 x 106 sec
- 9.63 x 106 sec
The correct answer is: 8.63 x 106 sec
Number of protons bombarded 
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