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General Thoughts: Engineering Studies (1 Viewer)

LlamaBoi

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For the bus question how did everybody do it?
I equated the work done to the kinetic energy, i.e. Fd = 0.5mv^2 and I got a reasonable answer of 15 km/h or something...not anywhere near 300's haha
 

mashups

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the coating of the cables is done through extrusion. but i agree this test was extremely difficult. i didnt even attempt to "finish off" the drawing of the aeroplane door hinge. that was bs
 

machine2035

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the coating of the cables is done through extrusion. but i agree this test was extremely difficult. i didnt even attempt to "finish off" the drawing of the aeroplane door hinge. that was bs
holy crap what a guess i mate.. I remembered seeing something about extrusion so I took a punt and looks like it payed off.

My hinge looked more like one that had been recovered after a plane crash.
 

Heydosaurus

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Mmm yes, you are right if you sum the vertical force you get 17.3 as vertical, however I also took moments from the right hand side reaction and got 17.3.. I think the angle support confused the f out of me
Wouldn't that be due to the fact that when you take a moment from a roller, you only end up with the vertical forces?
 

laser6628

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i did
PE=KE
mgh=.5mv^2
rearranged to
v=(2gh)^.5

where h=700sin40
 

machine2035

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Wouldn't that be due to the fact that when you take a moment from a roller, you only end up with the vertical forces?
I thought it's just that rollers always have the reaction perpendicular to the horizontal. I wasn't aware that if you take moments about a roller (or from it) that you only find vertical forces.

i did
PE=KE
mgh=.5mv^2
rearranged to
v=(2gh)^.5

where h=700sin40
Yep, I did the same.
 

Life4Never

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Wouldn't that be due to the fact that when you take a moment from a roller, you only end up with the vertical forces?
Moments can only find the vertical components. To find the NET force on a pin joint you need to consider forces horizontal and vertical. Don't have to worry about this on a roller as there is only force perpendicular to the plane its on.

What I did was use moments to find reaction at the roller support and then used sum of forces horizontal and vertical to get the pin joint reaction.
 

Bnr

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Moments can only find the vertical components. To find the NET force on a pin joint you need to consider forces horizontal and vertical. Don't have to worry about this on a roller as there is only force perpendicular to the plane its on.

What I did was use moments to find reaction at the roller support and then used sum of forces horizontal and vertical to get the pin joint reaction.
what did you get for CE or whatever they specified? I got something like 543N
 

Heydosaurus

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Moments can only find the vertical components. To find the NET force on a pin joint you need to consider forces horizontal and vertical. Don't have to worry about this on a roller as there is only force perpendicular to the plane its on.

What I did was use moments to find reaction at the roller support and then used sum of forces horizontal and vertical to get the pin joint reaction.
Yeah, that's right. Anyways, I ended up with a resultant force of 22 kN at 50-ish degrees, so hopefully the result ends up being satisfactory. =P

Also, I ended up with 9 kN (8.9 rounded up) for CE, too. Compression or tension?
 

harudew

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holy shit this is amazing. I have been shitting bricks all afternoon preparing to not get into uni, thankfully it truly was a bung hole of an exam.
 

machine2035

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Yeah, that's right. Anyways, I ended up with a resultant force of 22 kN at 50-ish degrees, so hopefully the result ends up being satisfactory. =P

Also, I ended up with 9 kN (8.9 rounded up) for CE, too. Compression or tension?
I think I had tension

I am so pissed I put down 17.3kN.. I think i originally put down 22.1 or whatever was and my force triangle is probally still there on the page.
 
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Life4Never

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Yeah, that's right. Anyways, I ended up with a resultant force of 22 kN at 50-ish degrees, so hopefully the result ends up being satisfactory. =P

Also, I ended up with 9 kN (8.9 rounded up) for CE, too. Compression or tension?
Yes it was 9 kN under compression.

Truss was pushing out.
 
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Capt Rifle

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i chose engineering studies in year 10 for prelim and it didnt even run at my school :( teacher left apparently
 

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