Rankers Physics

Nucleus: Practice Problem & Solution

The half life of radium is 1600 years. The fraction of a sample of radium that would remain after 6400 years (1991)
1/4
1/2
1/8
1/16

Short Solution (Best for NEET):

To solve this problem, we apply the core principles of Nucleus. Understanding the underlying formula is key to arriving at the correct answer below:

The number of half-lives is $n = 6400 / 1600 = 4$. The fraction of the sample remaining is $(1/2)^n = (1/2)^4 = 1/16$.

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