Physics Guide
Sign in
Back to Problems
F = ma (Final Problems)
Dimensional Analysis
FMA-2020B-25 · 2020B F = ma (AAPT)

2020 F = ma Exam B — Question 25

If a certain radioactive decay process happens n times per hour on average, then in any given hour, √ one expects to observe n decays with an uncertainty of n. Each hour can be assumed independent of the previous one, and n can be assumed constant over time. How many hours do you need to conduct the observation so that you can determine n within an uncertainty of 1%?
Source: Question 25, 2020 F = ma Exam B, © 2020 American Association of Physics Teachers (AAPT) and the U.S. Physics Team. Adapted by PhysicsTrainer: reformatted into a separate question and answer choices for online multiple-choice practice; any shared setup from nearby questions is repeated here. Not affiliated with or endorsed by AAPT or the U.S. Physics Team.