A community for students.

Here's the question you clicked on:

55 members online
  • 0 replying
  • 0 viewing

anonymous

  • 4 years ago

9. A particular radioactive substance has a half-life of 3 years. Suppose an initial sample has a mass of 200 mg. a) Write an equation that relates the mass of the radioactive material remaining to time. b) How much will remain after one decade, to the nearest hundredth? please do part b)

  • This Question is Closed
  1. anonymous
    • 4 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    Af = Ao (1/2) ^ t/h

  2. anonymous
    • 4 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    Af = 200 (1/2) ^ 10/3 i cant solve from here

  3. anonymous
    • 4 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    punch it in the calculator. i got 0.07; to the nearest hundredth

  4. anonymous
    • 4 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    the answer is 19.84 mg

  5. anonymous
    • 4 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    i got the answer too but i forgot how i did it

  6. razor99
    • 4 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    srry i know only grade 8 maths

  7. EarthCitizen
    • 4 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    h is the Planck's constant ryt ?

  8. anonymous
    • 4 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    h is the half life period

  9. anonymous
    • 4 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    half life means, it reduces to half in that period. So, from 200mg it goes to 100 mg in 3 years. In 6 years, it goes to 50 mg. In 9 years, it goes to 25 mg. In 10 years, it goes to.....that is the part of the equation I am not clear on (too long ago and too late/tired to recall).

  10. anonymous
    • 4 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    Try 25mg to the power of 2/3. Is that 19.84mg? I don't have scientific calculator.

  11. anonymous
    • 4 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    exactly but i gotta get the number 19.84. I got all the values just need to know how to put it in and no it doesnt work

  12. anonymous
    • 4 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    i got it. .

  13. anonymous
    • 4 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    Try...200*(1/2)^10/3

  14. anonymous
    • 4 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    punch in the calculator the first equation u've given

  15. anonymous
    • 4 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    @Jerwyn: how did you do it `:O

  16. anonymous
    • 4 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    find the cube root of .5 to tenth power, then multiply to 200

  17. anonymous
    • 4 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    My value is correct.

  18. anonymous
    • 4 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    200 times (1/2) to the power of 10/3. It gives you 19.84.

  19. anonymous
    • 4 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    First find 0.5 to the power of 3.333333. Then multiply by 200.

  20. Not the answer you are looking for?
    Search for more explanations.

    • Attachments:

Ask your own question

Sign Up
Find more explanations on OpenStudy
Privacy Policy

Your question is ready. Sign up for free to start getting answers.

spraguer (Moderator)
5 → View Detailed Profile

is replying to Can someone tell me what button the professor is hitting...

23

  • Teamwork 19 Teammate
  • Problem Solving 19 Hero
  • You have blocked this person.
  • ✔ You're a fan Checking fan status...

Thanks for being so helpful in mathematics. If you are getting quality help, make sure you spread the word about OpenStudy.

This is the testimonial you wrote.
You haven't written a testimonial for Owlfred.