Leaving and Junior Cert Revision

Hi all have just included some new websites you may find useful for revision for up coming exams.www.mocks.ie   www.scoilnet.ie

Also make sure to check exam tips for both Tech Graphics and DCG

Irish Times top tips to beat exam stress

1 Just study, don’t procrastinate. #RepeatAdvice @SueBo_

2 Put away the laptop. Get your parents to hide the battery so you won’t be tempted. @paddykell

3 Draw up a realistic timetable. Short, frequent study sessions. You need to be doing more than your homework.

4 Organise yourself. It’s never too late. Clear notes, tidy folders. Don’t stress yourself out. @Orlaith_Farrell

5 Don’t prioritise any one subject. All subjects should get equal time. Allow two hours each weekend for each subject and around 30-40 minutes per night for studying what was covered on that day in the classroom.

6 Print chief examiners’ reports for your subjects. They give sample answers which you can use as a guide for answering style. #studytips, @NatashaLynchEF

7 How much time do you spend on the internet? Half-an-hour in the morning, an hour in the evening? It all adds up. Two hours a day is 14 per week, 56 per month. Imagine if you were to spend just half of that revising.

8 Fewer late nights. The worst thing you can do at the weekends is spend the whole night up, and the whole day in bed. Try to get to bed by 1am at the latest on weekends, and get up early .

9 Divide up work with a friend, then meet up, photocopy each other’s notes, teach each other what you learned. #studybuddy, @NatashaLynchEF

10 Reading a book isn’t studying – it’s reading a book. Set a target: “I will revise this topic for 45 minutes”. Take notes as you go. Put away the books. Do an exam question. Now that’s study.

11 Get familiar with the layout of the exam paper. Some papers are tricky and complicated instructions could throw you on the day.

12 Don’t cut too many corners. Every year students emerge devastated because they listened to rumours about what was coming up. The truth is anything can come up. The papers are designed to be unpredictable.

13 Record your revision notes on a dictaphone, download onto your phone, revise on the move. #studytips, @NatashaLynchEF

14 Understand what you’re studying – or at least try. Rephrase in your own words when possible. Students who do well in exams don’t just vomit up facts, they demonstrate real understanding.

15 Keep the CAO in mind. Students tend to forget about what they put down on their CAO forms in the rush to study for the Leaving Cert. It’s no harm to keep thinking about what course you want to do, and keep researching different areas. @paddykell

16 Don’t talk about what study you’re doing and don’t listen to other people about what they’re doing. Lots of people lie about what they’re doing or not doing. The naturally brilliant friend who did nothing but somehow managed a B1 in the mocks is probably telling fibs about how hard they’re working.

17Eat! Porridge can be perfectly edible with some minor adjustments. Some fast ones include putting chocolate chips, bananas, peanut butter, or even molasses and strawberries on it. It takes the notion of inedible slop away and keeps you going all morning. @ClareReidy1

18 My friends and I started our own nerdy trend of dunking Nature Valley bars into yogurt pots, which I understand sounds revolting to some people, but it got us through. @ClareReidy1

19 Have something to divert your attention: being solely focused on a few days in June at this stage will fry your brain.

20 Exercise. Don’t study any later than 10pm, and if you can find the energy, go for a walk. It releases endorphins in your brain that make you feel good about yourself, and it clears your head after hours of studying. @paddykell

21 Peanut butter cups and chocolate bars with nuts are brilliant brain food, and addictive too. @ClareReidy1

22 Keep the exams in perspective. None of the following things will be dictated by how you do in the Leaving Cert: where you live, who you marry, how often you marry, how many icecreams you eat in your lifetime; your overall health and well-being; the number of stones that work their way into your shoes resulting in you repeatedly hopping about on one foot to remove them; the amount of love in your life.

Exam tips

Higher Level DCG Exam Tips

Layout of the Paper

Section A: 4 short questions on the Core topics, 20 marks per question, marked out of your best 3. Attempt all four.

Section B: 3 long questions on the Core topics. 45 marks per question, marked out of your best two. Read all three, do the two you are most confident on, if you have time at the end of the exam then attempt the third.

Section C: This section has 5 optional areas on Applied Graphics but you will only be marked on two of these. The areas covered are Structural Forms and Geological Geometry. Do not waste time attempting another question in this section.

The exam is 3 hours long which allows for around 35 minutes for each of the long questions and another 35 minutes for all of the short questions in Section A.

Make sure your sets are fully equiped before the exam.

Core Topics

Orthographic and Auxiliary Projection

Most questions on the course are given in an orthographic (ele, plan and end ele). A lot of questions will need to have auxiliaries to solve them. Know how to do first and second auxiliaries. Auxiliaries will be used to get true lengths, dihedral angles, point views, etc. (Page 51-53)

Solids in Contact

Know how to find points of contact in plan and elevation (page 83-84)

How to rotate spheres, cones, cylinders to the side of an object, bring them down and find them in their correct position in plan. (page 85-93)

Tracery – Given two solids that the new object touchs off but not the size of the new object. Use tracery to find the centrepoint. (page 97-102)

Tangent Planes – You will be asked to get the traces of the tangent plane. This is solves by cones. If the plane is lying against the cone (tangential to it) then the plane has to have the same angle as the side of the cone. But the same angled cone over the other solid, get the projections in plan to get the Horizontal Trace and then find the Vertical Trace in elevation (page 103-105).

Axonometric, Dimetric and Trimetric

Set up the axes as given in the question. Draw a level line, project and get the semi circle to allow you to set up the plan. Do similar for elevation or end elevation. Look at the 3D view given in the question to decide which elevation to draw and the direction the plan is drawn. If you get this wrong the object could end up facing in the wrong direction. Circles and curves are got by dividing up 60/30 and projecting the individual points to the middle to get the freehand curve (page 137-151).

Perspective

Gettiing the plan drawn, finding the spectator, picture plane, ground line, horizon line and vanishing points will get you nearly half the marks in this question.

Join outer parts of plan to the spectator, bisect this angle to get the line of vision, go 90° to this through whatever point given in the question to get the picture plane.

Go parallel to the edges of the plan from the spectator till it hits the picture plane and project up 90° to the picture plane to the horizon line to give the vanishing points.

Heights can only be marked off when its touching off the piture plane. If it doesn’t touch the picture plane then you need to continue the line/edge on till it does hit the PP, bring it up and mark the height off on that line, vanish it back to collect the point you were looking for.

Remember that all points have to go be joined from the plan to the spectator and brought up from where that its off the picture plane.

To get curves in perspective you need to divide up the circle/curve 60/30 and find the points individually (page 169)

Auxiliary Vanishing Points are used for sloping surfaces in perspective (like a roof). The angle is set from the line going from the spectator parrallel to the edge of the plan that was used to get the vanishing points. This will give a height that is used for marking above or below the vanishing point (depending what is needed). (page 174-181)

Conic Sections

Parabola – Eccentricity is equal to one which means the line of ecc. is always 45°.

Ellipse – Eccentricity is less than one so the line of ecc. is any angle less that 45°

Hyperbola – Eccentricity is greater than one so the line of ecc. is any anlgel greater than 45°

 

Eccentricity method is done the same way on all three sections. Ecc = PF/PD (See page 191)

Remember that 45° line from focus to the line of ecc. and straight down from there will give the vertex.

Know how to draw a tangent to a point on the curve and a point outside the curve for all three. (pages 192,194,203,204,214,215)

Double Hyberbola is drawn using a different method (page 211). The transverse axis goes from vertex to vertex. Remember the rule PF1-PF2 = transverse axis.

Learn the properties common to all conics (page 219-221)

Know how to get the centre of curvature for a point. (page 222)

Solids cut by Oblique Plane

Set up the ele and plan. Draw the traces. Project up along the horizontal trace to get an auxiliary view showing the cutting plane. Use this view to find the points needed to finish the plan. (page 234-239)

Rotate the points from the auxiliary to get the true shap of the cut surface out 90° from the plan. (page 240-241)

Get the traces of a plane by continuing on the edges in both plan and ele to find the traces. (page 243)

Intersecting Planes

The coordinates are given in the sequence in, up, down.

To get the dihedral angle you first need the line of intersection, then look 90° to that to get its true length. Then look along the true length to get the dihedral angle.

To get the line of intersection you may have to take either one or two level lines to get points on that line of intersection. Take the level line in ele so that it goes accross the two planes. Where it intersects the planes, drop the points down and find them in plan. Join them up according to the planes they are on and this will give two lines crossing in plan to give one point on the line of intersection.  (page 254-260)

Skew Lines

This is a follow on from intersecting planes but it only deals with two lines.

To get the line parallel to each other, you take a level line in ele, go parallel to the other line to give a point, drop that down and do the same in plan to give the strike line. This line is the angle of the auxiliary for getting the two lines parallel. (page 261)

At this point a few different things can be asked, shortest horizontal distance, shortest perpendicular distance, etc. (page 261-264)

Interpentration

On basic questions, intersection points can be got by using method like Limits, Radial Elements, Horizontal and Vertical sections. (page 274-283). Questions like these generally tend to come up in the short questions.

Long questions tend to be in the form of auxiliary plan method. Draw what you can of the ele and plan. Project the auxiliary plan by taking distance from the xy line down to points in the plan. Label all the points in all three view. Remember there will be a set of points where the object starts to go into the other and also a set where the object comes out the other side. Take one of these at a time. Point that are not found on the edges may need to have a generator drawn for them in the auxiliary, find that generator in ele and then find the point on that generator. (page 287-288)

Developments

Developments are the opening out of an 3D object to a flat 2D shape. (page 297-304)

An envelopment is the opposite of a development, given the flat shape and you have to draw the 3D shape. (page 309-329)

Applied Graphics

Structural Forms

This has three main parts, the hyperboloid of revolution, the hyperbolic paraboloid and the surface of translation piece.

Hyperboloid of Revolution – Know how to draw the curve in elevation by drawing the asymptote in plan and ele and finding the points from that (page 215). Know how to draw it if the top has some part cut off it and also if you are asked to get a true shape (page 221)

Hyperbolic Paraboloid – Divide up the edges to get the elements needed. Project these elements to all view and they will produce the curves needed. Know how to take a section view along a line. (page 218-220).

Get the plane director by using the level line method as in intersecting planes. This will give an auxiliary showing the plane director which is when all the elements are parallel to each other. This will also be the angle of the horizontal trace of the plance director if asked that. (page 224-228)

Surface of Translation – This is where a parabola slides down another parabola. It gives a shape that can be called a saddle roof. You need to know how to draw a parabola in a rectangle. Then it is a case of taking heights from the ele, dropping them down from the top of the parabola in end ele to give a width and using that width to give the points in plan. (page 230)

Additions to this is where parts of the piece are cut off or you have to work in reverse to get the curve in ele after taking the width from the plan to get the height needed in end ele. (page 231)

 

Geological Geometry

There are two main topics in this section, road geometry and mining geometry.

Road Geometry – You will have to know how to get cut and fill for a level and sloping road.

If you are cutting then the level of the road is below the contours on the map. If you are filling then the level of the road is above the contours on the map.

For a level road you come out parallel to the side of the road. The distances you come out is determined on wheither you are cutting or filling and what ratios there are for them. The ratio given is always multiplied by the intervals of the ground contours (normally 5m).

For a sloping road you will have to set up a cone (semi-circle) at the edge of the road. It will depend on if you are cutting or filling which part of the road this cone will be placed.

If you are cutting the cone will be on the low side of the road (Cut Low) 

If you are filling the cone will be on the high side of the road (Fill High)

Mining Geometry – Know how to get the dip, strike and thickness the traditional method by using the elevation and the level line method (page 263,270-275)

These can also be found just in the plan by dividing the line between the highest and lowest of the three points. It is divided into the number of intervals there are between these two points. (eg. 80 and 55 have 5 intervals of 5m between them so the line would be divided into 5 parts). The other point is then joined to its corresponding height on the divided line to give the strike line. The dip and thickness are found by looking along this strike line and taking an auxiliary (page 270-275)