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Homework Help: Embarrasing question :o

  1. Oct 19, 2004 #1
    Ok I don't have time to look at this problem for more then I already have... Help would put my (little) brain at ease....


    What is the velocity of the ball as it leaves the "sticky" part? It enters it with 4 m/s (and I'm sure that's correct) and the film of the ball is made at two frames per second... so that's just one second from the beginning to the end of the sticky section.

    I have the time and initial velocity but with no acceleration I don't know how. =\
  2. jcsd
  3. Oct 19, 2004 #2
    this is just a simple motion diagram, so hence
    you don't need any values to figure it out. it is totally conceptual. just look at the distance between the dots after the sticky part and you know the time in between those dots.

    hope this helps.
  4. Oct 19, 2004 #3
    So it leaves the sticky part with HALF the velocity it entered with? I'm just guessing here from the distance between the balls after the sticky part and before...

    *enters 2*

    It's correct. heh.

    Man I went crazy thinking of how to do this with an equation. I hope someone doesnt' post after me going "yes there is an equation actually." :rofl:

    Thanks. :)
  5. Oct 19, 2004 #4
    well here, since you got the problem right already i'll try to explain it better for you, so you understand it and will be able to get it easily the next time you encounter a question like it.

    It says that each dot is 0.5s apart(2 frames/second)
    so if you see that the distance between the dots is 1m as it comes off of the sticky part in order to get velocity, 1m/0.5s = 2m/s.

    You can also tell that once it leaves the sticky part there is no more acceleration, because the dots are equally spaced apart, so that means that their velocities are equal.
    Last edited: Oct 19, 2004
  6. Oct 20, 2004 #5
    Thanks again. :smile:
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