Module 6: Lesson 3

 

Self-Check 4

2. Question 18 on page 381 of the textbook
   

   18. To compare the relative risks of the two asteroids, the following equations can be used:
       
       

        

       
       
       Because the question is asking to compare the difference in Palermo scales, the equations can be rewritten like so:
       
       

        

       
       
       This can then be rearranged like so:
       
       

        

       
       
       Putting this in exponential form gives the following:
       
       

        

       
       
       By realizing that the relative risk of the second asteroid will be a reference point, the following values are known:
       
       

        

       P1 = −1.66
       
       

        

       P2 = −4.83
       
       

        

       R1 = ?
       
       

        

       R2 = 1
       
       Thus,
       
       The first asteroid has a relative risk of 103.17, or approximately 1479, times greater than the second asteroid.

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