A community for students.

Here's the question you clicked on:

55 members online
  • 0 replying
  • 0 viewing

anonymous

  • one year ago

It takes 0.225 seconds/revolution for a body of mass of 25 grams to rotate a circle with a radius of 15 cm. What is the centripetal force acting on that body?

  • This Question is Closed
  1. welshfella
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    force = m w r^2 F is in Newtons . mass in kgs and r in meters w = the angular velocity in radians / sec you can work this out from the given speed in revs / sec.

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

    how can I convert seconds/revolution to radians/sec?

  3. welshfella
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    1 rev = 2 pi radians it travels 2 pi radians in 0.225 secs so in 1 second it travels 2 pi / 0.225 radians

  4. welshfella
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    w = 8.89 pi rads/sec

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

    5x10^(-3) ?

  6. welshfella
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    now you need to convert 25 gms to kgs and 15 cms to meters.

  7. welshfella
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    what is 5x10^-3 ?

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

    the answer for the centripetal force?

  9. welshfella
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    hmm..

  10. welshfella
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    not quite - you need to multiply that by pi

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

    sorry i forgot to put pi, is it 0.0157?

  12. welshfella
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    yes thats in newtons

  13. welshfella
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    you can write it as 1.57 * 10^-2 N

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

    the answer is not in the choices :(

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

    i know other formulas maybe we can try that :)

  16. welshfella
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    oh - maybe i've gone wrong somewhere - its been a while since i did these what are the choices?

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

    \[T = 2\pi(r) \over v\]

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

    0.731 N, 749.47 N, 187.368 dynes, 2,924 N

  19. Jhannybean
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    Isn't centripetal force \[\sf F_c = \frac{ mv^2}{r}\]

  20. welshfella
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    yes where v = linear velocity

  21. anonymous
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    yes @Jhannybean :)

  22. Jhannybean
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    since centripetal acceleration = \(\sf a_c = \dfrac{v^2}{r}\)

  23. Jhannybean
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    cool, I still remember \(\checkmark\) haha

  24. welshfella
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    yea my memory has failed me here I should have checked

  25. welshfella
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    i was too confident lol!

  26. anonymous
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    \[T = \frac{ (2\pi(r)) }{ v }\]

  27. anonymous
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    |dw:1438464437672:dw|

  28. anonymous
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    is it correct?

  29. welshfella
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    my original equation should have been m w^2 r so F = 0.025 * (8.89pi)^2 * 0.15

  30. anonymous
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    oh it's 2.924 thank you :D

  31. welshfella
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    = 2.925 N

  32. anonymous
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    Can you help me with another problem ? :)

  33. welshfella
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    2.924

  34. welshfella
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    well i only have 10 minutes but see what i can do

  35. anonymous
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    thank you :)

  36. 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.