CBSE Class 12-science Answered
55Cs124(Z=55,A=124) has a half life of 30.8s.
(a) If we have 7.8 microgram initially, how many nuclei are presents? How many are present 2 min later?
(b) What is the activity at this time?
(c) After how much time will the activity drop to less than about 1 per second?