How to Draw Projections of an Inclined Rectangular Plane

TL;DR

To draw the projections of a rectangular plane inclined at 45 degrees to the vertical plane, start by marking its dimensions: 50mm by 30mm. The longer side should be positioned 10mm above the horizontal plane and the shorter side 20mm in front of the vertical plane. This setup results in the front view appearing as a square due to the incline.

Transcript

hello friends here in this video we are going to see a problem on projection of planes for that here is the question a rectangular plane abcd with length 50 mm and breadth 30 mm has its surface inclined to vp at an angle of 45 degree and perpendicular to hp such that the longer side bc is 10 mm above hp and shorter side a b is 20 mm in front of vp ... Read More

Key Insights

• 🫥 Inclined planes appear as lines in projections, while their true shape may be rectangular.
• 🫵 When a rectangular plane is inclined to the VP, it will have an apparent shape of a square in the front view.

Questions & Answers

Q: How do you draw the projections of a rectangular plane inclined to the VP at a certain angle?

To draw the projections, first, draw the XY line representing the HP. Then, project the longer side of the inclined plane (BC) above the HP by the given distance and mark the length of the sides. Finally, project the shorter side (AB) in front of the VP by the given distance to complete the front view.

Q: Why does the front view of the inclined plane appear as a square?

The front view appears as a square because the inclined plane, when projected onto the VP, becomes a line due to its negligible thickness. Therefore, only the outline of the rectangle is visible in the front view.

Q: How are the dimensions of the rectangular plane determined in the projections?

The dimensions of the rectangular plane are determined by projecting the points of the rectangle onto the projections. The length and breadth of the plane can be measured from these projections.

Q: How does the inclination of the plane affect the shape of the front view?

When the plane is inclined, the front view of the rectangular plane changes from a rectangle to a square. This is because the angle of inclination alters the orientation of the sides of the plane in the projections.

Summary & Key Takeaways

• A rectangular plane is given with dimensions of 50mm by 30mm and is inclined to the VP at a 45-degree angle, perpendicular to the HP.

• The longer side of the rectangle (BC) is 10mm above the HP, and the shorter side (AB) is 20mm in front of the VP.

• By drawing the projections, it is revealed that the front view of the inclined plane appears as a square.