Engineering

Saoirse61671

I was wondering if each question represented a certain topic in the book? We have never been taught theory in class. I got the Engineering Technology book and I'm trying to figure out what I should study. I also have some information on turbines and I've learned that.

óbriain1988

question 1 a will be short answer questions from anything,
question 1 b will be on the turbines.
generally this pattern is followed:
q2 = mechanical testing (a&b), NDT (c)
q5 = welding
q6 = plastics (a &b), processes like extrusion etc' (c)
q7 = machines like the lathe and milling machine etc'
q8 = mechanisms and circuits

you'll find the 2 chapters in the book will cover q2, i'd recommend starting with q5 though, cos it's only the one chapter to cover all the question 5. two chapters for q6 (i think it's all in the two anyway) and there's not much about q8 in the book. not sure about q3 or q4 cos i don't generally do them but they cover heat treatment and that i think.. it's in the book but i'm not sure what chapters cover what... don't usually do q7 either but i don't think you'll find all the stuff you need in one or two chapters... i'd say a lot of that stuff might be stuff you'd picked up on from using the machines anyway like...

hope that helps - we didn't do much theory either so it was a bit daunting as the start, but like we were told we'd have to do a bit ourselves and like when you look at it you don't need to know the whole book to get by like. i'd recommend starting on q5 anyway, easy topic to grasp, and only one chapter of the book and covers everything that'll come up in the question (except robotic welding but that's a choice in part c that you don't have to do... wouldn't be too hard to bluff if it came to it anyway like but if you cover the chapter well you wont need to).

Go n-éirí an t-ádh leat!

Saoirse61671

Thanks very much Exactly what I needed.

btj79

thanks man,really needed that!!!only took the subject up in 4th yr and started doin honous,but worst thing was i have no teacher!!!!
thanks a mil neways!!!

óbriain1988

just found this:
http://www.rte.ie/2fm/606/notes/2007/engineering_notes.doc
covers what is in each question a bit better.... kind of wishing i spent more time studying engineering than the internet now though...

Stereophonic

I was wondering if anyone could help me regarding a question on the Higher level Engineering exam tomorrow. All question I'm 100% on as I love Engineering but a question which gets me is the Tensile Test.

It's easy to draw the graph but only 1 mark is gained from the graph, the two questions are important. It involves Proof stress and Young's Modulus of Elasticity...

Heres the question from the 2005 papers Question 2B (i)(ii)


Heres the answer of the question the Exam Commission published



I'm confused how the answers are shown here. Could anyone tell me how to do that question step by step correctly and it would be much appreciated.

(i) Is 0.1% proof stress -- 1.00 on graph??
0.2% proof stress -- 2.00 on graph??
I know I draw a perpendicular line but finding the correct point...

(ii) Hardest part of question in my opinion.

Thanks for your help

mp3guy

The strain units of that graph are X1000, so realistically you've got 0.001, 0.002 and so on along the bottom. 0.1% proof stress is read from 0.001 strain, 0.2% from 0.002 strain and so on. That's just the way it is. So you want 0.2% proof stress, so you go to 2.00 (or 0.002) on the strain axis, then draw a line from the point parallel to where the graph is still proportional (ie not passed it's elastic limit). Then where this line hits the graph, you take a reading off your stress axis, and that's the answer.

Stereophonic

Cheers, would you explain how to do part (ii) if you get a chance too? Thanks

mp3guy

Young's Modulus is Stress/Strain, so you take any value that is still proportional (again before it breaks it's elastic limit) so take the second value and put 135 over 0.0015 (remember the strain values are x1000 so you have to divide it by 1000 first) and that will give you 90kN/mm²