Question

Radioactive Decay Beginning with 16 grams of a radioactive element whose half -life is 30 years ,the mass y(in grams) remaining after t years is given by

y=16(1/2)^t/30 ,t ≥ 0.
How much of the initial mass remains after 90 years?

Answer 1

Answer: 2 grams of the initial mass remains after 90 years.

Explanation:

The initial amount of the radioactive element is 16 grams. The half-life of the radioactive element is 30 years.

The mass y(in grams) remaining after t years is given by

y=16(1/2)^t/30 ,t ≥ 0

Therefore, the amount of the initial mass that remains after 90 years would be

y=16(1/2)^90/30

y=16(1/2)^3

y = 16 × 0.125 = 2 grams