How'd everyone go? (3 Viewers)

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kleenextissues1

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I cant even remember my answers to shit lol... but the (sqrt( 20^2 + 9^2) x f)/t sounds familiar
 
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For the escalator, Power = W/t
W= change in PE + KE
So in this case W = PE
Hence Power = mgh/25 (25 seconds was the time.)

Weight was 115, height was 9, use 10 for g.

P = 115x9x10/25
=414

As for the Amps one I'm really not sure...

I think R was 800 ohms, 2 was what I used for V so,
2=Ix800
I = 2/800
=2.5x10-3 or 0.0025
x10-3 is milli, so 2.5mA I think...
Great minds think alike ;)
 

Twiglet

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it was actually the MACRO-structure, it just wanted you to draw a cross section of a laminate. I did laminated glass= transparent polymer sheet sandwiched between sheets of annealed glass
 
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I did the stuff they make the A380's fuselage out of: duraluminum with fibre glass behind it
 

xblacksheepx

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but regardless of friction, wouldnt you have to work it out using the displacement from the starting point, and not just the height?
 

alen180sx

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What did you guys get for the reaction in the truss and the force in member x.
I got, reaction a= 14.1 force in x = 15.86(not 100%) but.
 

Skyge

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Some random answers off the top of my head

For the one with escalator with 115kg on it, answer was 414W I think.
I got 40 something mm for the extension of the cable in the last question.
Question about the current in the circuit with the lightbulb I got 2.5mA.

Any of these answers ring a bell with anyone else?
Exactly what I got :D
 

taeyang

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Some random answers off the top of my head

For the one with escalator with 115kg on it, answer was 414W I think.
I got 40 something mm for the extension of the cable in the last question.
Question about the current in the circuit with the lightbulb I got 2.5mA.

Any of these answers ring a bell with anyone else?
That is what I got.
 

miniwaybzz

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Jesus christ.... did anyone else fail hardcore at the drawings.. and ESPECIALLY the shear and bending moment diagrams? wtf was that? the force was like on a non given distance..
Macrostructure of laminates? are you fucking kidding me?
i had exact the same problems as you broo
 
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jonathanli

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cant believe people r saying this exam was easy. fucken hardest engineering one ive ever come across...
did anyone get like 23 or so KN for member X. In compression as well?
The only maths that fucked me over was that bloody bicycle...
 

SnowTau

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For the voltage question I'm pretty sure its 20mA.

Voltage = 18V
Voltage drop(voltage lost in circuit) = 2V
So voltage = 16v

V= IR

16=I*800

I = 0.02A = 20mA

Similar to question18 in 2009 hsc exam
Ah I knew there was something to do with the voltage drop... However, the voltage went from 18 to 2, making the voltage drop 16. So from what you've written that still makes V = 2? Unless you just mistyped it or something.
 

SnowTau

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cant believe people r saying this exam was easy. fucken hardest engineering one ive ever come across...
did anyone get like 23 or so KN for member X. In compression as well?
The only maths that fucked me over was that bloody bicycle...
hmm for X...
I used joint A as to get rid of it and the 2/3 members i cut that i didn't want, leaving the 15KN force downwards and the 5KN wind from memory...
So from A, (4x15)+(1.42x5)-(Xx8sin(20))

So, X = (4x15)+(1.42x5)/8sin(20)

=24.5KN, and it was in compression.

Not sure if 1.42 was the right height for the wind, however.
 

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