Projection of Points

 Projection of Point

In this post, we'll learn about the Projection of Point topic. The projection of points is a very basic and important topic to understand further topics in the engineering graphics subject.

Projection of a Point is all about showing the exact position of a point in a 2D plane that is actually in a 3D space.

There are some rules to be followed to show the correct position of a point in a 2D plane:

• The position of a point must be denoted by small letters.
• The position of a point that is given according to the Vertical Plane (VP) must be denoted without a single inverted comma ( ' ). (e.g. a, b)
• The position of a point which is given according to the Horizontal Plane (HP) must be denoted with a single inverted comma ( ' ). (e.g. a', b')

For a better understanding, we will see some examples of the projection of points.

Examples:

Draw the projections of the following points on the same x-y line.

I. Point A on V.P. and 30 mm below H.P.

II. Point B on H.P. and 20 mm in front of V.P.

III. Point C 20 mm above H.P. and 20 mm behind V.P.

IV. Point D is 25 mm below H.P. and 40 mm behind V.P.

V. Point E on H.P. and on V.P.

VI. Point F 40 mm above H.P. and 10 mm in front of V.P.

VII. Point G on V.P. and 35 mm above H.P.

Note: Don't forget to show the necessary dimensions!

I hope you understood the topic very well. If you have any doubts regarding the topic of examples, just let me know in the comment section! Till then keep learning, and keep improving!

Similar Problems:

1. A straight line AB is 60 mm long. It is inclined to H.P. and V.P. by an angle of 30° and 45° respectively. Point A is 30 mm above H.P. and 20 mm in front of V.P. Draw the projections of straight line AB. Find also the traces.
   
2. The elevation of line AB, 80 mm long, measures 55 mm. The end A is 20 mm above H.P. and 10 mm in front of V.P. Draw the projections of the line and find its true inclinations with H.P. and V.P. If the end B is 25 mm below H.P. and is behind V.P.
3. Find M of a line MN, which is inclined at 46° to H.P. and 20° to V.P. is 15 mm above the H.P. and it is in front of the V.P., while the end N is 60 mm in front of V.P. and is above H.P. Draw the projections of the line, find its true length if its plan length is 70 mm. Locate the points of intersection of the line with the principal planes.