10.2 Plans and Elevations
1. Plan is the image formed when solid is viewed from the top. Its orthogonal projection lies on the horizontal plane.
2. Elevation is the image formed when a solid is viewed from the front or from the side. Its orthogonal projection lies on the vertical plane.
3. In drawing plans and elevations of solids,
(a) Visible edges should be drawn using solid lines (──),
(b) Hidden edges whose views are blocked should be drawn using dashed lines (- - -).