Physics Ncert Solutions Class 12th Nuclei Physics NCERT Exemplar Solutions Class 12th Chapter Thirteen Class 12th Physics

A piece of wood from the ruins of an ancient building was found to have a ¹⁴C activity of 12 disintegrations per minute per gram of its carbon content. The ¹⁴C activity of the living wood is 16 disintegrations per minute per gram. How long ago did the tree, from which the wooden sample came, die? Given half-life of ¹⁴C is 5760 yr.

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Alok Kumar Singh | Contributor-Level 10

8 months ago

This is a Short Answer Type Questions as classified in NCERT Exemplar

Explanation- R= 12dis/min per gm and R₀= 16dis/min per gm T_1/2= 5760yr

R= $e^{- λ t}$ $e^{λ t}$

By taking log

$λ t l o g e = l o g \frac{R_{0}}{R}$

$λ t$ = log₁₀16/12 $* 2.303$

$t = \frac{2.303 (l o g 4 - l o g 3)}{λ}$

= 2.303 (0.6020-4.771)5760/0.6931

= 2391.20yr

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Physics Ncert Solutions Class 12th 2023

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