Author Question: What are radioactive decay rates in minerals affected by? A) temperature and pressure B) ... (Read 126 times)

plus1

  • Hero Member
  • *****
  • Posts: 676
What are radioactive decay rates in minerals affected by?
 
  A) temperature and pressure
  B) nothing
  C) variations in gravity and magnetism
  D) heat

Question 2

How have scientists determined the age of the Earth?
 
  What will be an ideal response?



rosiehomeworddo

  • Sr. Member
  • ****
  • Posts: 306
Answer to Question 1

Answer: B

Answer to Question 2

Answer: Eighteenth-century geologists, including James Hutton, applied scientific observations and principles to conclude that the geologic rock record requires that Earth be extraordinarily ancient. Lord Kelvin calculated Earth's age based on a conceptual model of how much the planet has cooled since its origin. His calculations suggested an age in the range of 20-40 million years. John Joly calculated the age of the oceans based on a conceptual model of how long it would take Earth's rivers to transport enough salt to account for the current saltiness of the ocean. His calculations suggested an age of 80-100 million years. Kelvin's and Joly's calculations were correct but included assumptions that could not be verified at the time of their work. Reconsideration of their assumptions shows that the ages they calculated are minimum values and, therefore, Earth must be still older.



Related Topics

Need homework help now?

Ask unlimited questions for free

Ask a Question


 

Did you know?

Essential fatty acids have been shown to be effective against ulcers, asthma, dental cavities, and skin disorders such as acne.

Did you know?

Cytomegalovirus affects nearly the same amount of newborns every year as Down syndrome.

Did you know?

Drugs are in development that may cure asthma and hay fever once and for all. They target leukotrienes, which are known to cause tightening of the air passages in the lungs and increase mucus productions in nasal passages.

Did you know?

Intradermal injections are somewhat difficult to correctly administer because the skin layers are so thin that it is easy to accidentally punch through to the deeper subcutaneous layer.

Did you know?

Eat fiber! A diet high in fiber can help lower cholesterol levels by as much as 10%.

For a complete list of videos, visit our video library