Chapter 19, Problem 19.20P

Interpretation Introduction

Interpretation:

To calculate the age of the charcoal BP

Concept Introduction:

Half-life is defined as the time taken for a radioactive substance to decay to half of its original amount.

When two disintegration rates of radioactive substance are given, one of dead substance ( whose age has to be found out) and the one of living substance, then the ratio of disintegration rate of dead : disintegration rate of living gives the fraction of the substance remaining.
This fraction can be used to calculate how many half-lives have elapsed from the formula:

  $fraction={(\frac{1}{2})}^n$ where n= number of half lives elapsed
This n when multiplied by the half life provides the age of the substance.