Home
Class 12
PHYSICS
The normal activity of living carbon-con...

The normal activity of living carbon-containing matter is found to be about 15 decays per minute for every gram of carbon. This activity arises from the small proportion of radioactive `" "_(6)^(14)C` present with the stable carbon isotope `" "_(6)^(12)C`. When the organism is dead, its interaction with the atmosphere (which maintains the above equilibrium activity) ceases and its activity begins to drop. From the known half-life (5730 years) of `" "_(6)^(14)C`, and the measured activity, the age of the specimen can be approximately estimated. This is the principle of `" "_(6)^(14)C` dating used in archaeology. Suppose a specimen from Mohenjodaro gives an activity of 9 decays per minute per gram of carbon. Estimate the approximate age of the Indus-Valley civilisation.

Text Solution

Verified by Experts

Given, normal activity `R_(0)`=15 decays per minute, Present activity R =9 decays per minute, and Half-life `T_(1/2)` = 5730 years
Since `R=R_(0)e^(-lamda t) implies R_(0)/R=e^(lamdat) or t=1/(lamda)ln R_(0)/R=1/(lamda)ln(15/9)`
But `lambda=0.693/T_(1/2) = 0.693/5730 Year^(-1)`
`therefore t= 5730/0.693 In(15/9)`year =4225 years
Promotional Banner

Topper's Solved these Questions

  • NUCLEI

    U-LIKE SERIES|Exercise Additional Question|9 Videos

  • NUCLEI

    U-LIKE SERIES|Exercise CBSE Based/Source -Based Integrated Questions|3 Videos

  • MOVING CHARGES AND MAGNETISM

    U-LIKE SERIES|Exercise SELF ASSESSMENT TEST (SECTION D)|1 Videos

  • RAY OPTICS AND OPTICAL INSTRUMENTS

    U-LIKE SERIES|Exercise SELF ASSESSMENT TEST (SECTION B)|3 Videos

Similar Questions

Explore conceptually related problems

The normal activity of living carbon -containing matter is found to be about 15 decay per minute for every gram of carbon. This activity arises form the small proportion of radioactive ._6C^(14) present with the ordinary ._6C^(12) isotope. When the organism is dead, its interaction with the atmosphare which maintains the above equilibrium activity, ceases and its activity begins to drop. form the known half life (=5730years) of ._6C^(14) , and the measured activity, the age of the specimen can be approximately estimated. This is the principle of ._6C^(14) dating used in archaeology. Suppose a spacimen form Mohenjodaro gives an activity of 9 decays per minute per gram of carbon. Estimate the approximate age of the Indus Vally Civilization.

The normal activity of a living matter containing carbon is found to be 15 decays per minute per gram of carbon. An archaeological specimen gives 6 decays per minute per gram of carbon. If the half -life of carbon is 5730 years, estimate the approximate age of the specimen.

For its activity , enzyme carbonic anhydrase requires :

A sample of wooden artifact is found to undergo 9 disintegration per minute per gram of carbon. What is the approximate age of the artifact? The half life of ._(6)^(14)C is 5730 years and radioactivity of wood recently cut is 15 disintegrations per minute per gram of carbon.

The activity of carbon-14 in a piece of ancient wood is only 12.5 % . If the half life period of carbon-14 is 5760 years, the age of the piece of wood will be

The activity of a radioactive isotope falls to 12.5% in 90 days. Compute the half life and decay constatn of isotope.

A radioactive sample’s activity drops to its one-third value in 80 minutes. Calculate the half-life of the sample.

The activity of a radioactive isotope is 3000 count per minute at a certai time and 2736 count per minute after 48 h later. The half-life of this isotope is