1. Not finding help here? Sign up for a free 30min tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Help quickly

  1. Jan 10, 2005 #1
    Help quickly plz

    I need help on this and quick!:
    A 4kg block is pushed alomng the ceiling with a constant apllied force of 85N that acts at an angle of 55 degrees with the horizontal. The block accelerates to the right at 6m/s^2. detremine the coefficient of kinetic friction between the block and the ceiling.

    ok i worked out the problem but i got the wrong answer. the values i got are: for normal force=69.62N. for ap=12.19. for af=6.19. for Ff=24.8N final answer=.356 and i need .816 what did i do wrong?
     
  2. jcsd
  3. Jan 10, 2005 #2

    dextercioby

    User Avatar
    Science Advisor
    Homework Helper

    Check the numbers in the text of the problem.That block should be flying...

    Daniel.
     
  4. Jan 10, 2005 #3
    what do u mean the numbers in the problem are right???
     
  5. Jan 10, 2005 #4

    dextercioby

    User Avatar
    Science Advisor
    Homework Helper

    1.U double posted.Two threads on the same problem.It's not fair... :grumpy:
    2.Yes,by the looks of it,the normal force should be zero and the body should raise from the ground...

    Daniel.
     
  6. Jan 10, 2005 #5
    Dex, its being pushed agaisnt the ceiling...
     
  7. Jan 10, 2005 #6
    wait but why if someone is pushing it on the ceiling? ur confusing me!
     
  8. Jan 10, 2005 #7
    OOHHHH I know, we forgot to account gravity, get the normal force, subtract or add gravity, im to tired to think, and then divide by Ff!!! see which one works
     
  9. Jan 10, 2005 #8

    dextercioby

    User Avatar
    Science Advisor
    Homework Helper

    Sorry,didn't read that part. :mad: You're right...It doesn't fly away...

    Daniel.
     
  10. Jan 10, 2005 #9
    wait what? how do i add or subtract gravity?
     
  11. Jan 10, 2005 #10

    learningphysics

    User Avatar
    Homework Helper

    Read the other thread Port.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?



Similar Discussions: Help quickly
  1. Help quick (Replies: 2)

  2. Quick Help! (Replies: 1)

  3. Quick help on this (Replies: 2)

  4. Quick Help! (Replies: 6)

Loading...