College Physics
College Physics
11th Edition
ISBN: 9781305952300
Author: Raymond A. Serway, Chris Vuille
Publisher: Cengage Learning
bartleby

Concept explainers

Question
Chapter 29, Problem 19P

(a)

To determine

The half-life in seconds.

(a)

Expert Solution
Check Mark

Answer to Problem 19P

The half-life is 6.95×105s .

Explanation of Solution

Given info: Half-life of I131 is 8.04 days.

1day=(24)(3600s)

The half life is,

t1/2=(8.04days)(24)(3600s)1day=6.95×105s

Conclusion:

The half-life is 6.95×105s .

(b)

To determine

The decay constant.

(b)

Expert Solution
Check Mark

Answer to Problem 19P

The decay constant is 9.97×107s1 .

Explanation of Solution

Given info: Half-life of I131 is 6.95×105s .

Formula to calculate the decay constant is,

λ=ln2t1/2

Substitute 6.95×105s for t1/2 in the above equation to get λ .

λ=ln26.95×105s=9.97×107s1

Conclusion:

The decay constant is 9.97×107s1 .

(c)

To determine

The activity in SI unit.

(c)

Expert Solution
Check Mark

Answer to Problem 19P

The activity in SI unit is 1.9×104Bq .

Explanation of Solution

Given info: Activity of I131 is 0.500μCi .

1Ci=3.7×1010Bq

The activity in SI unit is,

R=(0.500×106Ci)(3.7×1010Bq1Ci)=1.9×104Bq

Conclusion:

The activity in SI unit is 1.9×104Bq .

(d)

To determine

The number of I131 .

(d)

Expert Solution
Check Mark

Answer to Problem 19P

The number of I131 is 1.9×1010 .

Explanation of Solution

Given info: Activity of I131 is 0.500μCi .

Formula to calculate the number of I131 is,

N=Rλ

Substitute 0.500μCi for R and 9.97×107s1 for λ in the above equation to get R.

N=0.500μCi9.97×107s1=(0.500×106Ci)(3.7×1010Bq1Ci)9.97×107s1=1.9×1010

Conclusion:

The number of I131 is 1.9×1010 .

(e)

To determine

The number of half-lives completed and activity.

(e)

Expert Solution
Check Mark

Answer to Problem 19P

The number of half-lives completed is 5.

The activity is 0.200mCi .

Explanation of Solution

Section 1:

To determine: The number of half-lives completed.

Answer: The number of half-lives completed is 5.

Explanation:

Given info: Activity ( R0 ) of I131 at a given time is 6.40mCi . Time elapsed is 40.2 days. Half-life of I131 is 8.04 days.

Formula to calculate the number of half-lives is,

n=tt1/2

Substitute 40.2 days for t and 8.04 days for t1/2 in the above equation to get n.

n=40.2days8.04days=5

The number of half-lives completed is 5.

Section 2:

To determine: The activity.

Answer: The activity is 0.200mCi .

Explanation:

Given info: Activity ( R0 ) of I131 at a given time is 6.40mCi . Time elapsed is 40.2 days. Half-life of I131 is 8.04 days.

Formula to calculate the activity is,

R=R02n

Substitute 6.40mCi for R0 and 5 for n in the above equation to get R.

R=6.40mCi25=0.200mCi

The activity is 0.200mCi .

Conclusion:

The number of half-lives completed is 5.

The activity is 0.200mCi

Want to see more full solutions like this?

Subscribe now to access step-by-step solutions to millions of textbook problems written by subject matter experts!

Chapter 29 Solutions

College Physics

Knowledge Booster
Physics
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, physics and related others by exploring similar questions and additional content below.
Recommended textbooks for you
  • College Physics
    Physics
    ISBN:9781285737027
    Author:Raymond A. Serway, Chris Vuille
    Publisher:Cengage Learning
    College Physics
    Physics
    ISBN:9781305952300
    Author:Raymond A. Serway, Chris Vuille
    Publisher:Cengage Learning
    Modern Physics
    Physics
    ISBN:9781111794378
    Author:Raymond A. Serway, Clement J. Moses, Curt A. Moyer
    Publisher:Cengage Learning
  • Principles of Physics: A Calculus-Based Text
    Physics
    ISBN:9781133104261
    Author:Raymond A. Serway, John W. Jewett
    Publisher:Cengage Learning
    College Physics
    Physics
    ISBN:9781938168000
    Author:Paul Peter Urone, Roger Hinrichs
    Publisher:OpenStax College
    Physics for Scientists and Engineers with Modern ...
    Physics
    ISBN:9781337553292
    Author:Raymond A. Serway, John W. Jewett
    Publisher:Cengage Learning
  • College Physics
    Physics
    ISBN:9781285737027
    Author:Raymond A. Serway, Chris Vuille
    Publisher:Cengage Learning
    College Physics
    Physics
    ISBN:9781305952300
    Author:Raymond A. Serway, Chris Vuille
    Publisher:Cengage Learning
    Modern Physics
    Physics
    ISBN:9781111794378
    Author:Raymond A. Serway, Clement J. Moses, Curt A. Moyer
    Publisher:Cengage Learning
    Principles of Physics: A Calculus-Based Text
    Physics
    ISBN:9781133104261
    Author:Raymond A. Serway, John W. Jewett
    Publisher:Cengage Learning
    College Physics
    Physics
    ISBN:9781938168000
    Author:Paul Peter Urone, Roger Hinrichs
    Publisher:OpenStax College
    Physics for Scientists and Engineers with Modern ...
    Physics
    ISBN:9781337553292
    Author:Raymond A. Serway, John W. Jewett
    Publisher:Cengage Learning