The Theory of Nuclear Astrophysics Is That All the Heavy

question 17

Short Answer

The theory of nuclear astrophysics is that all the heavy elements like uranium are formed in the interior of massive stars.These stars eventually explode, releasing these elements into space.If we assume that at the time of the explosion there were equal amount of U-235 and U-238, how long ago did the star(s) explode that released the elements that formed our Earth? The present U-235/U-238 ratio is 0.007 0.[The half-lives of U-235 and U-238 are 0.7 * 109 yr and 4.47 * 109 yr.]

---

Definitions:

Effective Interest

The actual interest rate incurred on a loan or bond, reflecting the amortization of any fees or additional costs over the life of the loan.

Interest Revenue

Income earned from investments, loans, and other sources requiring the borrower to pay interest.

Bond Investments

Financial investments in debt securities issued by corporations or governments, which pay interest and are meant to be repaid at maturity.

Amortized

The gradual reduction of a debt over time by making regular payments that cover both principal and interest.