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Homework Help: Angel of inclination :-)

  1. Sep 3, 2008 #1
    1. The problem statement, all variables and given/known data / attempt

    I have to find the angel of inclination. I have a slide forming a triangle. We measured two points in the slide a meter apart. those two points are 23cm in one point and 35cm in another. All together it has a height for 58cm. However, I have no clue how to find the angle of inclination. I know I should use either sin or tan but I don't know how I plug in the values

    Attached is a picture.

    much thanks,


    http://img295.imageshack.us/img295/782/49775363zx5.th.jpg [Broken]
    Last edited by a moderator: May 3, 2017
  2. jcsd
  3. Sep 3, 2008 #2


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    It is not too clear from the picture, but are the two lengths 23 cm and 35 cm elevations of points on the slide above the horizontal, and the two points are 1 m apart as measured along the horizontal?

    Think about the relationship between tan [itex]\theta_i[/itex], where [itex]\theta_i[/itex] is the angle of inclination, and the legs of triangles with heights of 23 and 35 cm. If the 23 cm leg is at distance x from the vertex, i.e. where the slide intersects with the horizontal (ground, or reference plane), what is the distance to the 35 cm leg.

    Think of similar triangles sharing a common horizontal base, vertex and hypotenuse.
  4. Sep 4, 2008 #3
    So I should take the difference of distance between the two positions.

    That gets me 12. Should I then make a triangle and use .12m as my hypotenuse and 1m as my other side and just take the tan inverse of that?
  5. Sep 4, 2008 #4


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    Well, the 0.12 m would be the vertical leg and 1 m would be the other leg, but if one finds the tan-1 of the ratio (0.12/1), that would give the angle of inclination.
  6. Sep 4, 2008 #5
    ok thank you Astronuc,

    I'm new to my college physics classes and some easy things stump me!

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