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Some Kinematics Questions

  1. Dec 22, 2003 #1

    I have some problems with 4 questions regarding kinematics here! Any help would be greatly appreciated!

    Luv, miYu.

    Please visit this site for the questions!:

    http://sg.geocities.com/be_do_get/kinematics_unit2.doc [Broken]

    Attached Files:

    Last edited by a moderator: May 1, 2017
  2. jcsd
  3. Dec 22, 2003 #2

    Doc Al

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    Staff: Mentor

    Firstly, the link didn't work. Secondly, why not post your answers to the questions. Then you'll get plenty of help.
  4. Dec 23, 2003 #3
    1) remember that it is the weight component along the plane which makes the ball accelerate along the plane. In which diagram is the 'x-component' of the weight gradually getting smaller.

    2)Remember that the downward force is gradually equalled by the resistant forces (drag)

    3) Look at each of the 3 different stages of its motion separately, how will the rate of change of displacement change depending on the speed of the body?

    4)Its difficult to tell from the question whether the stone has an initial horizontal velocity. assuming it has. Firstly, you can split velocity distinctly into its horizontal and vertical components. The vertical is fine, it accelerates downwards at g m/s/s. In the real world, there is an acceleration for the x-component, namely air resistance. If there is no air resistance there is no external force acting on the body in the x-sense and therefore by Newtons first law its velocity will not change. That is why the horizontal motion is constant.
  5. Dec 28, 2003 #4
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