When a water-cooled nuclear power plant is in operation, oxygen in the water is transmuted to nitrogen-17. After the reactor is shut down, the radiation from the nitrogen-17 decreases in such a way that the rate of change in the radiation level is directly proportional to the radiation level. Required:
a. Write a differential equation that expresses the rate of change in the radiation level in terms of the radiation level.
b. Suppose that when the reactor is first shut down, the radiation level is 3 × 1017 units. After 60 s the level has dropped to 5.6 × 1013 units. Write the particular equation.
c. Sketch the graph of radiation level versus time.
d. It is safe to enter the reactor compartment
when the radiation level has dropped to
7 × 10–3 units. Will it be safe to enter the reactor compartment 5 min after the reactor has been shut down? Justify your answer.