Which of the following graphs best illustrates the relationship between:
the number of undecayed atoms in a radioactive sample (y-axis) and the time (x-axis)?
B.
D.
C.
A.
The activity of a radioactive sample drops from 800 counts/seconds to 200 counts/second in 24 hours.
The half life of the sample is:
12 hours.
24 hours.
3 hours.
8 hours.
Which of the graphs in the figure best represents the variation of count rate from a radioactive substance (Y) with time (X):
