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 74 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?

In inpatient settings, adverse drug events account for an estimated one in three of all hospital adverse events. They affect approximately 2 million hospital stays every year, and prolong hospital stays by between one and five days.

Did you know?

The horizontal fraction bar was introduced by the Arabs.

Did you know?

Inotropic therapy does not have a role in the treatment of most heart failure patients. These drugs can make patients feel and function better but usually do not lengthen the predicted length of their lives.

Did you know?

Drying your hands with a paper towel will reduce the bacterial count on your hands by 45–60%.

Did you know?

Today, nearly 8 out of 10 pregnant women living with HIV (about 1.1 million), receive antiretrovirals.

For a complete list of videos, visit our video library