* D.C.G. HL predictions / discussion / aftermath * (1 thread only please)

J_E

Kedo93 wrote: »

guys, can conics come up as a long question? God I hope it doesn't

yeah, I think it can. Remember answering a question on a partially complete parabola then asked to draw a tangential line.

PaulSul

Section B - Solids in contact , Planes and conical sections

Section C - Dynamic Mechanisms - Gears question

What people make of them that kinda what our teacher said ?

J_E

Gears as in a locus? Would be great if that came up.

coxy 132

Cydoniac wrote: »

Gears as in a locus? Would be great if that came up.

as in wheel pinion and rack i would say

Lmao_Man

Any sites with some DCG info on it ?

Examinations.ie obviously only has a few years of questions.

conlufc

im hoping for:section B-Planes, trimetric or perspective(though lines of interpretation seems most likely)
section c: im doing geologic and surface geometry.

although dcg is one of my better subjects iv a feeling tomorrows paper is gonna be cook!

J_E

coxy 132 wrote: »

as in wheel pinion and rack i would say

Ah damn, hate those. Going to practice a few tonight then.

fairenuf

Wonder will they ask Axonometric in section B?

conlufc

fairenuf wrote: »

Wonder will they ask Axonometric in section B?

doubt it..axonometric seems a bit 2 easy for section b
probably be either trimetric or dimetric

kev.f

coxy 132 wrote: »

as in wheel pinion and rack i would say

im doing Dynamic Mechanisms but we havnet covered gears??? should i be worried.

also what are the requlations with coulering/ shading drawings because i found for the mocks i was finished with plenty of time? is it frowned apon or will it lose you marks?

galwayman17..

biology over and done with...

now DCG time to sort this B!tch out! interpenetration, oblique planes, laminas if these dont come up i dont care im doing them anyway :mad:

Kedo93

kev.f wrote: »

im doing Dynamic Mechanisms but we havnet covered gears??? should i be worried.

also what are the requlations with coulering/ shading drawings because i found for the mocks i was finished with plenty of time? is it frowned apon or will it lose you marks?

Not at all! In fact, the examiners will love to see a bit of colour Just don't go overboard and make sure to use only bright colours so your construction lines are still visible. I would definitely use it for drawing locus' in Mechanisms and Displacement diagrams in cams, things like that.

Keen2win

Does anyone care to tell me how to do H.L. 2010, Q. C-2 (c)? It's about getting a plane director, I have no idea lol!

Lmao_Man

Do people expect the dihedral angle question to come up ?

And been told by a teacher on boards you can get a pass in HL even if you fail the drawing exam (with your project it can bump up to a pass)

RHunce

I'm going to take a wild stab in the dark and say it's going to be a bee eye itch of a paper and in section B there will be perspective, conics and solids in contact.. that's where my money is at.

john1741

RHunce wrote: »

I'm going to take a wild stab in the dark and say it's going to be a bee eye itch of a paper and in section B there will be perspective, conics and solids in contact.. that's where my money is at.

I wish, solids and perspective are what Im best at, and by best I mean I can do them

RHunce

anything thats not solids and conics would be great.. I'd still do them and pretty well but they are awful questions I think.

3 great ones for me would be perspective, intersecting planes and oblique planes.. That would be seeexxxy

Shanee.

Im hoping for these as a long question: Perspective, SOC, Oblique Planes, Econometric or the one with rebate.. as for part c mining geometry is pretty easy and the linkages and helix ones are fairly okay too..

G.J.

Am I the only one that's finding it hard to revise DCG? :P

conlufc

G.J. wrote: »

Am I the only one that's finding it hard to revise DCG? :P

no your not..i hate da hassle of setting up questions at home:pac:

ride-the-spiral

In section B i'm hoping for: Solids in Contact, Oblique Plane, and Intersecting Planes. Wouldn't mind interpenetration but it takes a while, and axonometric, di/trimetric would be alright. I'd hate to have to do conics or anything with development.

Doing geologic geometry and surface geometry, love those questions

Griffen262

G.J. wrote: »

Am I the only one that's finding it hard to revise DCG? :P

Its gone to the stage where your actually wasting your time drawing questions because there is so much to revise. Well thats me anyway, because im a cúnt that hasn't done much all year..

galwayman17..

Griffen262 wrote: »

Its gone to the stage where your actually wasting your time drawing questions because there is so much to revise. Well thats me anyway, because im a cúnt that hasn't done much all year..

dont be so hard on yourself man! your more of a pr!ck to me!:D:D

how you getting on?

MikeHough

galwayman17.. wrote: »

dont be so hard on yourself man! your more of a pr!ck to me!:D:D

hahahaha. Gas man
:pac::pac::pac::pac:

PaulSul

RHunce wrote: »

I'm going to take a wild stab in the dark and say it's going to be a bee eye itch of a paper and in section B there will be perspective, conics and solids in contact.. that's where my money is at.

galwayman17.. wrote: »

biology over and done with...

now DCG time to sort this B!tch out! interpenetration, oblique planes, laminas if these dont come up i dont care im doing them anyway :mad:

#




I have a feeling you could be right

Griffen262

Got a question, no doubt ye'll help me out.

Having a look at laminas here and saw this Q in the samples in the exam papers.

(c)Determine the angle of inclination of the line of intersection to the vertical(or in some questions the horizontal) plane.

Vertical Plane Question

Horizontal plane Question


Notice question (d), find the dihedral angle...Now, I know how to set up these questions and find the line of intersection and also the dihedral angle, like this example..

But these questions (c)'s are putting me off, Do you find the trace's of the planes? and thus the dihedral angle?...like this example?

God, id love to have the teacher beside me for a few hours looking over things..


P.S Galwayman17...

kev.f

was just looking at them questions. all the other parts of it are grand but not sure bout the angle of the line of intersection

was doing it like on page 233 of the red book. using the like of intersection and anyone of the other lines to creat VTH

havent a clue it this is right though. anyone any thoughts

Chemistry Ftw

Do people reckon that intersecting planes will come up again for the third year in a row???

J_E

I have no idea how to do gears, and if it comes up I'll be forced to do it! How hard is it to learn?

Lmao_Man

Lmao_Man wrote: »

Do people expect the dihedral angle question to come up ?

And been told by a teacher on boards you can get a pass in HL even if you fail the drawing exam (with your project it can bump up to a pass)

Last bit is true isn't it ? Have no chance of passing otherwise.

galwayman17..

Griffen262 wrote: »

Got a question, no doubt ye'll help me out.

Having a look at laminas here and saw this Q in the samples in the exam papers.

(c)Determine the angle of inclination of the line of intersection to the vertical(or in some questions the horizontal) plane.

Vertical Plane Question

Horizontal plane Question


Notice question (d), find the dihedral angle...Now, I know how to set up these questions and find the line of intersection and also the dihedral angle, like this example..

But these questions (c)'s are putting me off, Do you find the trace's of the planes? and thus the dihedral angle?...like this example?

God, id love to have the teacher beside me for a few hours looking over things..


P.S Galwayman17...

im feeling the love griffen262.!:p

did you not get any sheets on these nea the latter stage of th year atol?


sorry but cant honestly say i dont no what to do! laminas is a question i just do without thinkin! dont really know whats going on at all! but that sounds really confusing. and check the marking schemes on the website. it should help out sort of!

Chemistry Ftw

Griffen262 wrote: »

Got a question, no doubt ye'll help me out.

Having a look at laminas here and saw this Q in the samples in the exam papers.

(c)Determine the angle of inclination of the line of intersection to the vertical(or in some questions the horizontal) plane.

Vertical Plane Question

Horizontal plane Question


Notice question (d), find the dihedral angle...Now, I know how to set up these questions and find the line of intersection and also the dihedral angle, like this example..

But these questions (c)'s are putting me off, Do you find the trace's of the planes? and thus the dihedral angle?...like this example?

God, id love to have the teacher beside me for a few hours looking over things..


P.S Galwayman17...

Hi there! This is VERY simple. Have you found the line of intersection between the tow planes? If so, project lines perpendicaular to the L.O.I from the plan. Take all your measurements from the elevation and plot your points. When you have plotted your points you should extend your L.O.I back down to your x2 y2 line and the angle it makes with it is your inclination angle!

ride-the-spiral

To find the inclination of a line to the horizontal plane what you want to do is set up an auxiliary elevation where the line is visible as a true length. So set up an x1y1 line parallel to the line of intersection on the plan, then draw the auxiliary. The inclination will be the angle between the line and the x1y1 line.

Similar thing for the inclination to the vertical, except use an auxiliary plan.

The dihedral angle has nothing to do with these part (c)'s, and you just carry on as normal.

Donerkebab

ride-the-spiral wrote: »

To find the inclination of a line to the horizontal plane what you want to do is set up an auxiliary elevation where the line is visible as a true length. So set up an x1y1 line parallel to the line of intersection on the plan, then draw the auxiliary. The inclination will be the angle between the line and the x1y1 line.

Similar thing for the inclination to the vertical, except use an auxiliary plan.

The dihedral angle has nothing to do with these part (c)'s, and you just carry on as normal.

thats the long way of doing it

Griffen262

galwayman17.. wrote: »

im feeling the love griffen262.!:p

did you not get any sheets on these nea the latter stage of th year atol?


sorry but cant honestly say i dont no what to do! laminas is a question i just do without thinkin! dont really know whats going on at all! but that sounds really confusing. and check the marking schemes on the website. it should help out sort of!

Wouldn't of got anything, So no. It has never actaully came up in the L.C yet, so no answers or marking schemes available..Its just a question that bugging me, so any of ye A1'ers here, feel free to enlighten me.

I doubt this this question will come up, but as i said, its getting on my tits!

hairybacon

Interpenetration likely? Anyone do the developments and label yokes? No idea how to do them.

minymc

Griffen262 wrote: »

Got a question, no doubt ye'll help me out.

Having a look at laminas here and saw this Q in the samples in the exam papers.

(c)Determine the angle of inclination of the line of intersection to the vertical(or in some questions the horizontal) plane.

Vertical Plane Question

Horizontal plane Question


Notice question (d), find the dihedral angle...Now, I know how to set up these questions and find the line of intersection and also the dihedral angle, like this example..

But these questions (c)'s are putting me off, Do you find the trace's of the planes? and thus the dihedral angle?...like this example?

God, id love to have the teacher beside me for a few hours looking over things..


P.S Galwayman17...

Hopefully this should help you;

1. Find the line of intersection as normal using a level cutting plane in elevation
2. Project an auxiliary elevation from your plan to find the line of intersection as a true length (taking your heights from the original elevation)
3. Once you have found the true length of the line of intersection, continue the line on to cut the X1Y1 line, this will give you the true inclination of the line of intersection to the horizontal plane because you have projected an auxiliary elevation

If you wanted to find the true inclination of the line of intersection to the vertical plane you would have to project an auxiliary plan - this would mean after finding your line of intersection as normal, find where the line of intersection is in elevation (bring it up from plan), carry out steps 2 and 3 above except this time you would be projecting from elevation rather than plan!

Hope that put an end to your problem! Difficult to explain without being able to sketch it!

With regard to predictions for the exam - I reckon oblique plane, interpenetration and either lamina/perspective could be strong runners!

Best of luck to everyone sitting the exam!

galwayman17..

hairybacon wrote: »

Interpenetration likely? Anyone do the developments and label yokes? No idea how to do them.

developments in surface geometry?

Chemistry Ftw

Does anyone know a good website for Geologic and Surface Geometry sections beside examination.ie???

ride-the-spiral

Griffen262 wrote: »

Wouldn't of got anything, So no. It has never actaully came up in the L.C yet, so no answers or marking schemes available..Its just a question that bugging me, so any of ye A1'ers here, feel free to enlighten me.

I doubt this this question will come up, but as i said, its getting on my tits!

There's an explanation of it on p42 of the red book.

J_E

Honest question...what are the chances of gears coming up? I'll have to learn them because I've never done them before and the calculations look insane to have ready in one day.

hairybacon

galwayman17.. wrote: »

developments in surface geometry?

Page 297 of the red book.

cookier

Chemistry Ftw wrote: »

Does anyone know a good website for Geologic and Surface Geometry sections beside examination.ie???

It should be on the t4.ie website I think..

hairybacon

Cydoniac wrote: »

Honest question...what are the chances of gears coming up? I'll have to learn them because I've never done them before and the calculations look insane to have ready in one day.

Well this is the first I heard of them- the book says you have to construct epicycloidal gear profiles. As far as I can see all the ones in the book are nearly the same, I'm just going to read over pages 194/5 and let her be lucky!

J_E

hairybacon wrote: »

Well this is the first I heard of them- the book says you have to construct epicycloidal gear profiles. As far as I can see all the ones in the book are nearly the same, I'm just going to read over pages 194/5 and let her be lucky!

Hopefully it won't come up but I can't take any chances. I just wish I was aware of this before...

Alternatively I could learn Geologic Geometry. Opinions?

Donerkebab

Griffen262 wrote: »

Got a question, no doubt ye'll help me out.

Having a look at laminas here and saw this Q in the samples in the exam papers.

(c)Determine the angle of inclination of the line of intersection to the vertical(or in some questions the horizontal) plane.

Vertical Plane Question

Horizontal plane Question


Notice question (d), find the dihedral angle...Now, I know how to set up these questions and find the line of intersection and also the dihedral angle, like this example..

But these questions (c)'s are putting me off, Do you find the trace's of the planes? and thus the dihedral angle?...like this example?

God, id love to have the teacher beside me for a few hours looking over things..


P.S Galwayman17...

Here ya go

galwayman17..

hairybacon wrote: »

Page 297 of the red book.

thats just practise tbh. you get into a rythym doing it.! this exam tomorrow im $hitting a brick for it!

galwayman17..

Cydoniac wrote: »

Hopefully it won't come up but I can't take any chances. I just wish I was aware of this before...

Alternatively I could learn Geologic Geometry. Opinions?

geologic geometry isnt that hard but i dont really understand your situation, havnt read the comments,

but ya the first part is simple with the roadworks and the 2nd part (boreholes) is a lil bit harder but not that much.

J_E

galwayman17.. wrote: »

geologic geometry isnt that hard but i dont really understand your situation, havnt read the comments,

but ya the first part is simple with the roadworks and the 2nd part (boreholes) is a lil bit harder but not that much.

Basically at the moment I can only do Dynamic Mechanisms and Assemblies, but I've never done the gears question. While it hasn't come up the past two years I'm kind of paranoid that it will come up and I'm unsure what to do.

dannyirishman

Can you use A2 paper?