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Archived Homework set #3

  1. Oct 6, 2014 #1
    I said I'd put up questions for the set, but for now I'll just set the thread up.
     
  2. jcsd
  3. Oct 6, 2014 #2
    Does anybody have any info on P3-7? Am I missing a conversion? Because I keep on getting 'e' as the answer... Not 'M' which is listed in the solutions...
     
  4. Oct 6, 2014 #3
    Could you please tell me what steps you took in order to get "e"? Incidentally, I read your post too quick and I thought you needed help with H3-7 and I now have that one figured out. In case anyone needed a hand with that one.
     
  5. Oct 7, 2014 #4
    #3-4) is the "roller-coaster" question that Mr. Randall mentioned previously. The mass is 5.00 kg, h1= 5.00 m, h2= 3.20 m, h3= 2.00 m, g= 9.8 m/s^2. Using what we know about Gravitational Potential Energy and Kinetic Energy (Plus conservation of energy too ), we can solve for the speed of the bead at points B and C (or 2 and 3 depending on how you want to see it). Using this method I was able to solve part a) for Vb and Vc, which I found to be approx. 5.9 m/s and 7.7 m/s respectively. I would like to hear some feedback on whether or not you got the same answer and we can discuss how our answers were achieved.
     
  6. Oct 8, 2014 #5
    I'm going to attempt to load a PDF with homework hints ... see if those help at all.
    There is an error in my answers for #15 .. see later post.
     

    Attached Files:

    Last edited: Oct 14, 2014
  7. Oct 8, 2014 #6
    Those values look accurate to me. I think it should be 3 sigs.
     
  8. Oct 9, 2014 #7
    Thanks for the homework help link, time start my weekend aka physics lab and hw set
     
  9. Oct 14, 2014 #8
    OK, mistake in the answer values for #15:
    (b) x = 1.77 m
    (c) F = 35,400 N
     
  10. Mar 17, 2015 #9
    Here's a link to a vid that practically works one of the homework problems:

     
  11. Mar 17, 2015 #10
    Another worked example of impulse and momentum vectors:
    In this one, an astronaut tosses a wrench ... astronaut goes one way, wrench goes the other ... how fast?
     
  12. Mar 17, 2015 #11
    Here's a live demo of a ballistic pendulum:
     
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