 Solution

ID: past-exam-of-the-chemistry-course-of-the-year-4-of-the-natural-sciences-course-of-the-university-of-cambridge/2022/paper-1/5/d/ii/solution

For

p > 0

, equivalently

0 \leq q < 1

n = 1 \sum \infty q^{n - 1} p = \frac{p}{1 - q} = 1.

Thus absorption probability is one. The qualification matters: if

p = 0

, the process alternates between

B

and

I

forever and never reaches

A

 New to topics? Read the docs here!