1. A stone is thrown vertically upward from the ground with an initial velocity of 128 ft/sec. How long it will take for the stone to reach the ground? 2. The rate of decay of radium is proportional to the amount present at any time. The half-life of radium is 1690 years and 20 mg of radium are present now. How much radium will remain after 1690 years?

1. A stone is thrown vertically upward from the ground with an initial velocity of 128 ft/sec. How long it will take for the stone to reach the ground? 2. The rate of decay of radium is proportional to the amount present at any time. The half-life of radium is 1690 years and 20 mg of radium are present now. How much radium will remain after 1690 years?

Principles of Physics: A Calculus-Based Text

5th Edition

ISBN:9781133104261

Author:Raymond A. Serway, John W. Jewett

Publisher:Raymond A. Serway, John W. Jewett

Chapter30: Nuclear Physics

Section: Chapter Questions

Problem 34P

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B. Carbon-14 is a radioactive isotope of carbon that has a half-life of 5600 years. It is used extensively in dating organic material that is tens of thousands of years old. Model the differential equation of the decay of the isotope if m is the mass and t is the time Calculate the constant using the half-life time. What fraction of the original amount of Carbon-14 in a sample would be present after 10,000 years? i) ii)
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Q2(C). Use A(t )= A0ekt to determine how much of a 100-g sample is present after 250 years if the half-life of Uranium-232 is 68.9 years.
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