# Introduction

The topic we will be revising this week is Laminar Planes. Laminar Planes are part of the Oblique Planes section of the course. The constructions in this topic are fundamental can could be used for a number of topics such as Interpenetration (have you tried to solve one yet? Study Tip 10: https://youtu.be/SFHvXu4d_Bc). Laminar Planes questions can come up in Section A, Section B and they are also an important part of Geologic Geometry and Surface Geometry in Section C. As you can see it is vital that you understand Laminar Planes as it's concepts and constructions will almost certainly be on your Leaving Cert exam paper come June.

# Syllabus Learning Outcomes

(Leaving Certificate Design and Communication Graphics Syllabus, 2006)

# What you Need to Know!

### Ordinary Level (and Higher Level)

- Find the Edge View of a Laminar Plane.
- Find the True Shape of a Laminar Plane.
- Find the Line of Intersection between 2 Laminar Planes (Given 1 point on the Line of Intersection or no points on the Line of Intersection).

### Higher Level

- Find the Dihedral Angle between 2 Intersecting Laminar Planes.
- Draw the shortest Horizontal Line, Perpendicular Line, or line at a given inclination to a Laminar Plane given a point outside the plane.
- Find the Traces of a Plane given a Laminar Plane
- Find a Laminar Plane's True Inclination to the Vertical and Horizontal Planes

# Practice Questions

## Practice Textbook Questions

(Anderson, 2014)

- P172 Q9
- P172 Q10

## Practice Exam Questions

There are a lot this week so if you don't have time to complete them all don't worry but make sure you come back to them!

- 2017 HL A-3, A-4, B-2
- 2016 HL B-1
- 2015 HL A-3
- 2014 HL B-1
- 2013 HL B-1
- 2010 HL B-3

I hope you're still working through your DCG revision and I'm sure if your following this revision guide every week are are getting more and more confident with the drawing topics that you completed last year. Good luck with this week's questions and as always if you have any questions please leave them in the comments section below.

### REFERENCES

Leaving Certificate Design and Communication Graphics Syllabus. (2006). Dublin: The Stationary Office.

Anderson, D. (2014). *Graphics in Design and Communication: One Volume Edition*. Dublin: Gill & Macmillan.