An ancient rock is obtained from an excavation inside a mine. It is found that the ratio of the number of (stable) 4ºAr atoms present to the number of (radioactive) 4°K atoms is 0.002. Assume that all the argon atoms were produced by the decay of potassium atoms, with a half-life of 1.25 109 y. How old is the rock?

An ancient rock is obtained from an excavation inside a mine. It is found that the ratio of the number of (stable) 4ºAr atoms present to the number of (radioactive) 4°K atoms is 0.002. Assume that all the argon atoms were produced by the decay of potassium atoms, with a half-life of 1.25 109 y. How old is the rock?

Modern Physics

3rd Edition

ISBN:9781111794378

Author:Raymond A. Serway, Clement J. Moses, Curt A. Moyer

Publisher:Raymond A. Serway, Clement J. Moses, Curt A. Moyer

Chapter13: Nuclear Structure

Section: Chapter Questions

Problem 25P

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