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Homework Help: Help with multiple choice for physics test

  1. May 4, 2010 #1
    1. The problem statement, all variables and given/known data

    Trying to find out correct answers to multiple choice.

    2. Relevant equations


    3. The attempt at a solution

    I have an important physics test coming up and I tried the multiple choice questions from a past paper, but unfortunately there is no memo. Could someone please check/help me with my answers (Question 1 of the attached pdf).

    1.1 A (cause 40 degrees optimum angle for longest range)

    1.2 Not sure

    1.3 A (tension vector to the top left, tension component to the left: centripetal a, mg down)

    1.4 Have no idea

    1.5 Have no idea
  2. jcsd
  3. May 4, 2010 #2
    No attachment.
  4. May 4, 2010 #3
    Oops I forgot. Here it is
  5. May 4, 2010 #4
  6. May 4, 2010 #5
    Sorry run into slight glitch but its now attached

    Attached Files:

  7. May 4, 2010 #6
    1.1) No, 45 degrees is the optimal angle for range. But that does not even matter since the question is asking about time. You need to find an equation for the time in the air.

    1.2) Draw the forces to find the acceleration in each case. Then use kinematics to solve the time it takes to travel the length of the incline. Then use the fact that it takes double the time when friction is involved.

    1.3) Doesn't the tension (diagonal top left) include the component going straight up and the component going to the center of the circle?

    1.4/1.5) Think about what will cause it to tilt and come up with some equations, at least try.
    Last edited: May 4, 2010
  8. May 5, 2010 #7
    Oh ok. Can you give me the answers cause I need to check them to see if I got them right
  9. May 5, 2010 #8
    Only if you show your work.
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