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Homework Help: Newtons second law force problem

  1. Oct 26, 2003 #1
    A 69 kg block is pushed along the celing with a constant applied force of 1300N that acts at an angle of 56 degrees with the horzontal. The block accelerates to the right at 8m/s^2. What is the magnitude of the normal force the ceiling exerts on the block? Answer in units of N.

    and

    A merry-go-round makes one complete revolution in 16s. A 19.7kg child sits on the horizontal floor of the merry-go-round 3.58 m from the center. Find the child's acceleration. Answer in units of m/s^2.
     
    Last edited: Oct 26, 2003
  2. jcsd
  3. Oct 26, 2003 #2

    HallsofIvy

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    Strange- you seem to have neglected to show what YOU have already done on these problems.
     
  4. Oct 26, 2003 #3
    ok for problem 1)
    i did fnet = ma
    i think i have it now
    i did Fsin56 - mg = N

    and i have no clue where to start on the second problem
     
    Last edited: Oct 26, 2003
  5. Oct 26, 2003 #4

    HallsofIvy

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    The child's mass is irrelevant. Since the radius for the child is 3.58 meters, the child is going around a distance of 2π (3.58) meters every 16 s. From that you can determine the childs speed in mets per second. Of course that's a constant speed but the direction is changing. Do you have a formula for the the acceleration toward the center given the speed around the circle?
     
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