Table of Contents
- 1 Why is first angle projection preferred over third angle projection?
- 2 Why 2nd and 3rd angle projections are not used?
- 3 Why do we use 1st angle projection?
- 4 What is difference between true shape of section and apparent shape of section?
- 5 Which angle of projection is recommended?
- 6 What is the difference between first and third angle projection?
- 7 Is this a first angle or third angle projection?
Why is first angle projection preferred over third angle projection?
The orthographic projection system is used to represent a 3D object in a 2D plane….Difference between First Angle Projection and Third Angle Projection :
| SR.NO | First Angle Projection | Third Angle Projection |
|---|---|---|
| 1 | The object is placed in the first quadrant. | The object is placed in the third quadrant. |
What is the difference between 1st angle projection and 3rd angle projection?
In third-angle projection, the view of a component is drawn next to where the view was taken. In first-angle projection, the view is drawn on the other end of the component, at the opposite end from where the view was taken.
Why 2nd and 3rd angle projections are not used?
In Mechanical Engineering,drawings are made either in first angle projection or in third angle projection. Overlapping projection views create confusion in the drawing. Therefore 2nd angle projection system is not used. Similarly when object is placed in 4th quadrant both top and front view will overlap.
Which is incorrect about 3rd angle projection?
Explanation: As the object is in third quadrant and the front view projects on a vertical plane and top view projects on horizontal plane. And for representing the projection the horizontal plane has to turn 90 degrees in clockwise direction. The top view will be above the front view. 5.
Why do we use 1st angle projection?
They are used to obtain engineering drawings for clarity. For the first angle projection the observer is placed on the left side of the object which puts the object right between the plane of projection and the observer.
Which of the following is true for the first angle projection?
Explanation: First angle projection means the object is placed in first quadrant and the top view of the object is below the front view so the bottom view is above the front view.
What is difference between true shape of section and apparent shape of section?
Sectional view : The projection of the section along with the remaining portion of the object is called a Sectional View. Projection on the other plane is called apparent section. 2. True shape of the section : Projection of the section on a plane parallel to the section plane will show the true shape of the section.
What is the difference between orthographic projection and isometric projection?
Isometric, or pictorial drawings, which represent an object in a three dimensional fashion by showing 3 surfaces of the object in one drawing. Orthographic, or plan view drawings, which represent an object in a two dimensional fashion by showing each surface of the object in its actual shape.
Which angle of projection is recommended?
Here 1st angle represents the initial stage in forming projection of planes so 1st quadrant represents 1st angle projection. Explanation: First angle projection is recommended by Bureau of Indian Standards but USA and other countries recommend third angle projection.
Which of the following are the appropriate views of the given object in a first angle projection?
Which of the following are the appropriate views of the given object in a first angle projection? Explanation: In first-angle projections, we have object positioned in first-quadrant between two principal planes. Here, the front view, top view, and the left-hand side view are enough to require the object completely. 9.
What is the difference between first and third angle projection?
In first angle projection, object lies between observer and the plane of projection. In third angle projection, plane of projection lies between the observer and the object. 3. In first angle projection, the plane of projection is assumed to be non-transparent. In third angle projection, the plane of projection is assumed to be transparent.
What does mean by first angle and third angle projection?
In First angle projection, the object lies in between observer and plane of projection. Whereas in the third angle projection, the projection plane lies in between observer and Object. We will keep adding more updates and examples on the first angle and third angle projection system.
Is this a first angle or third angle projection?
Difference between First and Third Angle Projection Basics of First and Third Angle Projection. First Angle Projection is one of the ways of representing three-dimensional objects with respect to two dimensions which is commonly used in Europe Representation of First and Third Angle Projection. Plane of First and Third Angle Projection. View Sequence of First and Third Angle Projection. First vs.
What is the definition of the first angle angle projection?
1st angle projection is a type of orthogonal projection system where the object is placed in the first quadrant in such a way that it lies in between the observer and the plane of projection. First angle projection system is widely used in European countries.