This topic contains a solution. Click here to go to the answer

Author Question: A radioactive material initially is observed to have an activity of 1000 decays/sec. If nine hours ... (Read 29 times)

vicotolentino

  • Hero Member
  • *****
  • Posts: 552
A radioactive material initially is observed to have an activity of 1000 decays/sec. If nine hours later it is observed to have an activity of 125 decays/s, what is its half-life?
 a. 1/2 hour
  c. 3 hours
  b. 8 hours
  d. 1 hour

Question 2

Neglecting recoil of the gold nucleus, how much kinetic energy must an alpha particle (charge = 2  1.6  10-19 C) have to approach to within 1.95  10-14 m of a gold nucleus (charge = 79  1.6  10-19 C)? (ke = 8.99  109 Nm2/C2 and 1 MeV = 1.6  10-13 J)
 a. 14.6 MeV
  c. 18.2 MeV
  b. 11.7 MeV
  d. 22.7 MeV



Related Topics

Need homework help now?

Ask unlimited questions for free

Ask a Question
Marked as best answer by a Subject Expert

joechoochoy

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

C

Answer to Question 2

B





 

Did you know?

It is difficult to obtain enough calcium without consuming milk or other dairy foods.

Did you know?

When intravenous medications are involved in adverse drug events, their harmful effects may occur more rapidly, and be more severe than errors with oral medications. This is due to the direct administration into the bloodstream.

Did you know?

More than nineteen million Americans carry the factor V gene that causes blood clots, pulmonary embolism, and heart disease.

Did you know?

The term bacteria was devised in the 19th century by German biologist Ferdinand Cohn. He based it on the Greek word "bakterion" meaning a small rod or staff. Cohn is considered to be the father of modern bacteriology.

Did you know?

The Babylonians wrote numbers in a system that used 60 as the base value rather than the number 10. They did not have a symbol for "zero."

For a complete list of videos, visit our video library