Engineering Graphics - Demystified

Whichever branch we opt for in Engineering, we have to study engineering graphics.

For most of the pupil this is a subject which is tough to score marks.

The teaching method of graphics is as follows (followed by most of the tutors)
Teacher will explain the rules to draw a top view or front view
Students will by heart the rules and learn to draw using T square

The end result -> Students will never get answers to following questions.

1. What is graphics?
Graphics is the representation of objects as images. In this representation the dimensionals details or the size of the object will also be quite evident.

2. Why graphics is needed?
Two people can communicate clearly only if they know the same language. Even then quite often there can be communication gap, which means that the listener might have understood things in a different way than the speaker indented.
If two persons don't know the same language then how can the speaker tell the listener that he is telling something about a car. The speaker can show the image of car to the listener.
Yes images have no barriers. There is no language for images. If you can see images then it conveys everything clearly.
But by just showing image of a table, can a carpenter make a table?
No, Because he don't have information on what size it should.

So the image need to contain size (dimensional) details also in a specific unit. Seeing this image the maker of the table can make the table exactly of the same size which is intended.

"GRAPHICS IS A UNIVERSAL LANGUAGE FOR ENGINEERS"

Why front view/ top view side view is needed?
A rectangle can easily be represented in a single image showing the length of each side. This is two dimensional figure, since it has only two dimensions, the length and breadth.
Now how can we draw a rectangular prism in a sheet of paper. Rectangular prism means it has got length, breadth and height.
Assume that we place the prism on a flat surface. Now look at it from the top in such a way that we are not able to see its sides. We can see only a rectangle now. It is possible to draw the rectangle showing its length and width on a paper. This means from the top the original 3D object looked like a 2D object, which can be represented in a paper.
Now look the prism from the front in such a way that we cannot see the top. We can see another rectangle now. This can also be drawn on a paper.
Ok now we have two images for a single object. We have to draw it in certain order according to standard conventions. Otherwise how can a third person know which is the view from the top and which is the view from the front.

More questions related to graphics to follow