Gaps in knowledge? Fill them in here! (1 Viewer)

[PimpPyro]

This is basically a place to ask questions and get answers.

I shall kick this off. Does anyone have info on:
"Control technology
- digital technology" (Engineering syllabus)
Thanks,
Dan.

 

[fakingtheday]

Digital Control Technology

In a nutshell a computer monitors, senses changes and then uses technology to rectify problems. I use ABS where a computer monitors the braking stress on each wheel, and if it senses a wheel locking from the braking it redistributes this force to other wheels.

Benefits include increased safety of cars, braking efficiency and in turn a greater fuel efficiency.

 

[PimpPyro]

Thanks!

Thanks Faking

 

[fakingtheday]

Just incase i'd also have this one up your sleeve. Regnerative Braking is widely used in Europe now. WHere powere used by trains when braking is sent back up into the grid and to power other trains on the grid. Just from memory. Just remember:

Senser -> Controller -> Resdistribution (or whatever)

 

[PimpPyro]

That's pretty easy, physics can help me with that one.

 

[fakingtheday]

*doesn't do physics*

 

[PimpPyro]

Damn, physics is pretty useful in engineering, chem likewise! Especially when you have a shitass engineering teacher.

 

[dodgeviper]

conrol devices are easy, pretty much anythign digital cruise control etc, as it has one choice or another
some knowledge that i need filling in specific detail is grain structures for
-all heat treatment
-all castings

and quick question to you guys, how much detail are you memorising on cast adn wrought irons, as well as brazz and bronze alloys. as there is is stacks of info on it but it seems trival.

also im confused with tv synchronisation if anyone can help me with that.
thnx gl studying

 

[Mat_Aussie]

Here are some notes on heat treatment that i found

so its not mine, but i hope it helps

Mat

 

[fakingtheday]

Annealing - large equiaxed grains, soft ductile
Normalising - refined grains, tougher
Hardened - asicular grains. Matrensite. very hard and brittle
Tempered - no inner stresses, hard and tough
Surface hardened; carburising: higher carbon content on the skin makes it harder
flame induction and quenching gives martensite skin. harder

 

[dblanche]

Units For Pressure Questions and Young Modulus

What Units For the Hydraulic Jack questions do you use to get MPa and how many MPa is 1 GPa

Also for youngs Modulus do you use 'm' or 'mm' with Newtons

 

[fakingtheday]

you have to use m for everything in engineering!

a MPa is 1 x 10^6 and a Gpa is 1 x 10^9

 

[richz]

hello,

can sumone help me with Q13a 2004 hsc, the luggage one. My answer is 159 N.

PS fakingtheday what book/notes do u use to study for in engineering, u have any tips for the exam

thnx

 

[fakingtheday]

xrtzx: i got 187N as the force, it's just the addition of the FF which is equal to 0.3 x (cos10 x300) and component down the plane which is sin10 x 300.

i use rochford when i need it but my teacher is the best resource going dude.

 

[dodgeviper]

where did u get rockford?

 

[Husayn]

I've got the Rochford exam questions one, although its from the syllabus 2000 and hence its from the engineering science course, they don't seem to match what has been coming in the last 2-3 years in the HSC.

 

[dblanche]

Q12 (b)

What did everyone get for the 2004 HSC Q12 (b) for the reaction at support 1 and the force in member A

I got 2740N for the reaction at support 1 but I don't know how to get the force in member A


Can someone Please help me!!

 

[dblanche]

Q12 (b) 2004 hsc

Still Having trouble with this question but I got 519N for the force in member A

 

[fakingtheday]

that's the right answer

 

[dblanche]

thanks for the help but now I have another Question to ask for the Q14 (a) 2004 HSC again

Here is the question:

Question 14 — Lifting Devices (10 marks)
(a) A crane uses a DC electric motor to lift a mass of 250 kg vertically from the
ground. After 18 seconds the mass is 20 metres off the ground with an upward
velocity of 2 ms−1.




(i) Determine the average power required by the motor to perform this
lifting operation.
Power = ................................ kW





I dont know how to calculate the work, I think it is 250kg x 10ms x 20m= 50000Nm

If I know what the work is then I can put it into the formula Power = Work / Time


Which by me would equal 50000/ 18 = 2777.8


Could someone please tell me what the actual answer is