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Cant figure out how to do this problem?

  1. Mar 3, 2007 #1
    Cant figure out how to do this problem??

    A person pushes a 14kg lawn mover at constant sped with a force of 88N directed along the handle, which is at an angle of 45 degress to the horizontal. (a) draw the Free-body diagram showing all forces acting on the mower. (b) Calculate the horizontal friction force on the mower, then (c) the normal force exerted vertically upward on the mower by the ground. (d) What force must the person exert on the lawn mower accelerate it from rest to 1.5m/s in 2.5 seconds, assuming the same friction force?

    This is a problem on my practice PCAT test for Pharmacy school. And its been a while since I have had physics so any help would be appreciated.

  2. jcsd
  3. Mar 4, 2007 #2


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    Well, what have you done? Have you drawn a free body diagram at least? Which parts of the question have you attempted?
  4. Mar 4, 2007 #3
    Because the angle of the handle is 45 degrees, the force along the handle of 88N can be broken up into a horizonal force or square root of 2x88; and a vertical downward force of the same amount. I.e. 1.414 x 88 = 124.4 N.

  5. Mar 4, 2007 #4

    er, thats close but sin and cos 45 are actually= sqrt(2)/2=1/sqrt(2)=.707

    On the other post, I mentioned what the Normal force is, so can you calculate it? Hint: weight plus vertical component of push but directed upwards. So what is weight?
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