In very old stars, heavy metallic elements like uranium (U), osmium (Os), and iridium (Ir) are...
Fantastic news! We've Found the answer you've been seeking!
Question:
Transcribed Image Text:
In very old stars, heavy metallic elements like uranium (U), osmium (Os), and iridium (Ir) are hard to come by. (Usually, these elements are created during supernovae, when stars die in an epic explosion.) In 2001, there was a star detected in our Milky Way that had trace (but still detectable) amounts of these elements in it, suggesting the star was very old and may have only been formed by one previous supernovae in the history of our universe. The following ratios for the amounts of U, Os, and Ir in the star were measured at the time of the study: 238 U (²05) = -2.19, log10 log10 2381 18 U Ir = = -2.10. (la) (lb) Theoretical arguments from nuclearsynthesis models (whose complexity is far beyond this class) suggest that the initial ratio of these amounts at the time the star formed were 2381 (200) = -1.27, Os = -1.30. log10 log10 2381 Ir (2a) (2b) a. The amount of isotope 238 U in the star exponentially decays in time with a half-life of 4.47Gyr. (That's 4.47 x 10⁹ years.) Suppose the initial amount of 238 U in the star is 238 Uo. Find a for- mula for the amount of 238U in the star for all time t> 0 measured in giga-years. Note: your answer should only have one unknown constant in it, which is 238 Uo. b. The elements Os and Ir are stable elements, meaning the amount of these elements in the star does not change in time. Using (la) to estimate the present amount of 238 U in the star and (2a) to estimate the initial amount of 238U in the star, how old is the star? Don't forget units in your answer! c. If instead (1b) is used to estimate the present amount of 238 U in the star and (2b) is used to estimate the initial amount of 238 U in the star, how old is the star? Don't forget units in your answer! d. Taking an average of your answers from (b) and (c), what is a reasonable estimate for the age of our universe? Don't forget units in your answer! In very old stars, heavy metallic elements like uranium (U), osmium (Os), and iridium (Ir) are hard to come by. (Usually, these elements are created during supernovae, when stars die in an epic explosion.) In 2001, there was a star detected in our Milky Way that had trace (but still detectable) amounts of these elements in it, suggesting the star was very old and may have only been formed by one previous supernovae in the history of our universe. The following ratios for the amounts of U, Os, and Ir in the star were measured at the time of the study: 238 U (²05) = -2.19, log10 log10 2381 18 U Ir = = -2.10. (la) (lb) Theoretical arguments from nuclearsynthesis models (whose complexity is far beyond this class) suggest that the initial ratio of these amounts at the time the star formed were 2381 (200) = -1.27, Os = -1.30. log10 log10 2381 Ir (2a) (2b) a. The amount of isotope 238 U in the star exponentially decays in time with a half-life of 4.47Gyr. (That's 4.47 x 10⁹ years.) Suppose the initial amount of 238 U in the star is 238 Uo. Find a for- mula for the amount of 238U in the star for all time t> 0 measured in giga-years. Note: your answer should only have one unknown constant in it, which is 238 Uo. b. The elements Os and Ir are stable elements, meaning the amount of these elements in the star does not change in time. Using (la) to estimate the present amount of 238 U in the star and (2a) to estimate the initial amount of 238U in the star, how old is the star? Don't forget units in your answer! c. If instead (1b) is used to estimate the present amount of 238 U in the star and (2b) is used to estimate the initial amount of 238 U in the star, how old is the star? Don't forget units in your answer! d. Taking an average of your answers from (b) and (c), what is a reasonable estimate for the age of our universe? Don't forget units in your answer!
Expert Answer:
Related Book For
Materials and process in manufacturing
ISBN: 978-0471656531
9th edition
Authors: E. Paul DeGarmo, J T. Black, Ronald A. Kohser
Posted Date:
Students also viewed these mathematics questions
-
You want to either create a product or service that doesn't exist (for example, a dishwashing robot) or you can use a new product or service that has just recently been launched. It is fine if you...
-
What influence over the quality of a product or service do customers really have?
-
Select a product or service and role-play a sales callfrom the approach to the closewith another student. Have one member of the team act as the salesperson with the other member acting as the...
-
Because of its seemingly insatiable "addiction to oil," in the past the US was and still purchases crude oil primarily from countries in the Middle East. It is said that each day, the average payment...
-
P (A) = 0.68, P (B | A) = 0.30, and P (B | A) = 0.02. Find P (A), P (A and B) , and P (A and B). Use these to construct a probability table. Now use the table to find the following: P (B| A), P (B|...
-
Investigate the utilization of advanced geotechnical instrumentation and monitoring systems, such as inclinometers, piezometers, and ground-penetrating radar (GPR), for characterizing soil-structure...
-
Under the assumptions of the linear model, the vertical spread in a residual plot will be about the same across the plot. In Exercises 9 and 10, determine whether the statement is true or false. If...
-
After graduating from college, you and your friends start selling birdhouses made from recycled plastic. The idea has caught on, as shown by the following sales gures: MONTH DEMAND March..............
-
The records of Alliston Aviation Supply Inc. include the following accounts for inventory of aviation fuel at December 31, 2020: (Click the icon to view the records.) Requirements 1. Prepare a...
-
Fairbanks Express is a luxury passenger carrier in Alaska. All seats are first class, and the following data are available: Number of seats per passenger train car ........... 60 Average load factor...
-
Farm Friends has these account balances at December 31, 2020: Accounts Payable 9,500 Accumulated Amortization-Equipment Note Payable, Long-Term Accounts Receivable 28,000 Cash 7,300 Prepaid Rent...
-
Provide a detailed analysis of group dynamics, including the issues of informal roles, norms, and networks; interpersonal conflict; and leadership and decision-making in groups. In addition, provide...
-
Participants (pID, role, lname, fname, affiliation, email, lunch) Talks (tID, pID, title, topic, abstract, sID) Sessions (sID, description, topic, room, start, stop, mID) Write an SQL query which...
-
Healthy Dulce manufactures kale salads. For January, it budgeted to purchase and use 14,500 kilograms of kale at $1.04 per kilogram; budgeted output was 54,375 salads. Actual purchases and use for...
-
3. Mr. Lago, Filipino, married, died on Nov. 30, 2020. The assets, charges and obligations of the spouses are shown below: Communal Property Investment in a Business Partnership Family Home (house...
-
What are the key neurobiological differences observed in individuals with neurodevelopmental disorders like autism spectrum disorder (ASD) ?
-
Performance Products Corporation makes two products, titanium Rims and Posts. Data regarding the two products follow: Rims Posts Direct Labor- Hours per unit 0.40 Annual Production 20,000 units 0.20...
-
The manager for retail customers, Katie White, wants to hear your opinion regarding one business offer she has received from an entrepreneur who is starting a mobile phone app called Easy Money. The...
-
What are some of the different material characteristics or responses that have been associated with the term hardness?
-
Explain how you could determine if your ordinary bathroom scale is linear and has good repeat accuracy, assuming the scale is analog.
-
Why is brazing an attractive process for joining dissimilar materials?
-
Show that for an ideal gas, \(\left(\frac{\partial E}{\partial V} ight)_{T}=0\), and for a van der Waals gas, \(\left(\frac{\partial E}{\partial V} ight)_{T}=\frac{a n^{2}}{V^{2}}\).
-
Explain some important methods for the estimation of the fugacity coefficient of a pure substance.
-
Estimate the residual entropy, enthalpy and internal energy at 298 K and 10 bar for nitrogen obeying the van der Waals equation of state, given that T c = 126.2 K and P c = 34.0 bar.
Study smarter with the SolutionInn App