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Here's a question, today I had on my test

  1. Dec 8, 2004 #1
    You fill in with a, b, c, d, e, or f. It can be more than 1.
    The image is in the attachment

    a. speed up
    b. slow down
    c. constant speed
    d. maximum speed
    e. minimum speed
    f. speed is zero

    What does the object do at each point if it is rotating clockwise in a vertical circle?

    Here's what I put.

    1. d
    2. b, because of gravity
    3. e, f
    4. a

    referring to the circle in the attachment

    6. The tension in the string at the bottom of the circle equals.
    a. mg - Fc
    b. Fc - mg
    c. mg + Fc
    d. Fc
    e. mg

    7. The tension in the string at the top of the circle equals
    a. mg - Fc
    b. Fc - mg
    c. mg + Fc
    d. Fc
    e. mg

    6 -> c 7 -> b

    Anyway that's what I put, but I'd like to know other people's opinions to know if I got it right for sure.

    Attached Files:

  2. jcsd
  3. Dec 9, 2004 #2
    Your first answer seems to be correct. I'm not an expert in physics, but it looks good to me.
    Forgive me if this is an ignorant question, but what does the "string" refer to? Is it referring to the circle itself? Is the object attached to a string of some sort?
  4. Dec 9, 2004 #3

    #3 should just be e. THe velocity cannot be zero there because [tex] a_{c} = \frac{v^2}{r} [/tex] And [tex]a_c[/tex] must be greater than or equal to g for the object to not fall and keep swinging.

    All your other answers were correct.
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