Suppose a radioactive nucleus has a half-life of 2 min. and suppose the counting rate at t = 0 is 3000 counts/s.

a. What is the counting rate after 2 min?

b. After 6 min?

c. After 10 min?

d. After 20 min?

e. What is the mean life of this nucleus?

f. Suppose that the Geiger counter detects 10% of all the radioactive decays.

What is the total number of radioactive nuclei at time t=0?

g. What is the total number at t 2 min?

h. How many nuclei decay in the first 2 minutes?

i. What is the initial decay rate?

j. Why is the answer in h. not equal to the answer in i. times 120 sec?

Expert Solution

genius_generous answered 2 years ago

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