Answer:
THE AMOUNT OF THE SAMPLE REMAINING AFTER 5 HOURS IS 1250 CPM
Explanation:
A sample has a half life of 100 minutes. To solve for the amount remaining after a given amount of 10000CPM decay in 5 hours, we use the formula:
Nt = No * (1/2)^t/t1/2
Where:
Nt = amount remaining = unknown
No = initial amount = 10000 CPM
t = time elapsed for decay = 5 hours = 60*5minutes = 300 minutes
t1/2 = half life = 100 minutes
Putting the values into the formula, we have:
Nt = 10000 * (1/2)^ 300/100
Nt = 10000 * (1/2)^3
Nt = 10000 * 0.125
Nt = 1250 CPM
The amount of the sample remaining after 5 hours is 1250 CPM.
