Unit 1ProjectionsEASY

True Length and Inclinations of a Line

A line AB, 80mm long, has its end A 20mm above HP and 25mm in front of VP. End B is 50mm above HP and 60mm in front of VP. Determine the true length and its inclinations with HP and VP.

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Solution Diagram

Solution diagram for True Length and Inclinations of a Line
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Step-by-Step Construction

  1. 1

    Plot the projections of points A and B using given coordinates

  2. 2

    Draw the front view (FV) and top view (TV) of the line

  3. 3

    Apply the theorem: True Length = √[(FV length)² + (difference in distances from VP)²]

  4. 4

    Calculate angle with HP using tan θ = (height difference) / (TV length)

  5. 5

    Calculate angle with VP using tan φ = (depth difference) / (FV length)

  6. 6

    Verify using graphical method with auxiliary projection

Pro Tips

  • Always verify your measurements with a scale before finalizing the drawing
  • Use construction lines lightly and darken the final solution
  • Label all important points and reference lines clearly