If the physical half-life of sulfur-35 is 87.1 days, and the biologic half-life in the testicle is 632 days, what is its effective half-life in this organ?

I know i have to find the time and then the half-life.

But im having trouble finding the time

A(t)=Ao x e ^ (-0.693) (t) / T1/2 [half=life]

I'm thinking to just divide 632 days by 87.1 days to determine the half-life

25

To find the effective half-life in the testicles, you need to determine the time it takes for the activity of sulfur-35 to decrease by half in this organ.

The formula you have provided:
A(t) = Ao * e^(-0.693 * (t) / T1/2)

Let's break down the formula:

A(t) represents the activity of sulfur-35 at time t.
Ao is the initial activity of sulfur-35.
e is the base of the natural logarithm (approximately 2.71828).
-0.693 is a constant derived from the decay constant of radioactive substances.
(t) represents the time that has elapsed.
T1/2 is the half-life of sulfur-35.

To solve for t in the formula, we can rearrange it as follows:

t = (ln (A(t) / Ao)) * (-T1/2 / 0.693)

From the given information, we know the physical half-life of sulfur-35 is 87.1 days and the biological half-life in the testicles is 632 days.

Plugging these values into the formula:

t = (ln (1/2)) * (-632 / 87.1)

ln (1/2) is equal to -0.693 (since ln (1/2) = -0.693).

t = -0.693 * (-632 / 87.1)

Calculating this expression:

t ≈ 5.029

Therefore, the effective half-life of sulfur-35 in the testicles is approximately 5.029 days.