Physics 2009 JAMB Past Questions - Question 46: If the decay constant of a radioactive substance is 0.231s^1 , the half-life is

Correct Answer

A

Explanation

The half-life (t1/2) of a radioactive substance can be calculated using the decay constant (λ) with the following formula:

t1/2 = ln(2) / λ

where:
- t1/2 is the half-life.
- ln(2) is the natural logarithm of 2, approximately equal to 0.6931.
- λ is the decay constant.

In your case, the decay constant (λ) is 0.231 sâ�»¹. Plugging this value into the formula:

t1/2 = ln(2) / 0.231 s¹
t1/2 ≈ 3.01 seconds

So, the half-life of the radioactive substance with a decay constant of 0.231 s¹ is approximately 3.01 seconds.