suggested exam solutions

[orangez]

itute solutions are up for anyone interested:

http://www.itute.com/physicsline/ph_vcaa_exam1_sol_2008.pdf

It says the file is damaged

Serious? I downloaded it.

[bigtick]

on itute physics forum as well

[deano]

What ever happened with photonics?

[orsel]

Structures and materials q9 aka 'da bridge':

Assuming equilibrium:
- Reaction force from ground at point Z must be upwards (ignoring horizontal component of friction).
- Only way to balance this upwards force is a downwards compressive force from beam ZX (ZY has no vertical component)
- Hence ZX = compression

- Only way to balance forces at point X is if XY is under tension (since we already know ZX is compressed and pushing upwards)

- Back to point Z, ZX still has a horizontal component to the 'left'. A force to the 'right' must be supplied. Thus ZY is under tension so that it pulls to the 'right'.


btw I reckon they made this year too easy...I'm a bit concerned about whether they'll accept my explain-type answers; other than that full marks lol.

[Mao]

Structures and materials q9 aka 'da bridge':

Assuming equilibrium:
- Reaction force from ground at point Z must be upwards (ignoring horizontal component of friction).
- Only way to balance this upwards force is a downwards compressive force from beam ZX (ZY has no vertical component)
- Hence ZX = compression

- Only way to balance forces at point X is if XY is under tension (since we already know ZX is compressed and pushing upwards)

- Back to point Z, ZX still has a horizontal component to the 'left'. A force to the 'right' must be supplied. Thus ZY is under tension so that it pulls to the 'right'.


btw I reckon they made this year too easy...I'm a bit concerned about whether they'll accept my explain-type answers; other than that full marks lol.

that's a very good explanation thank you.

I was resolving forces at the point Y. XY under tension made me think that ZY need to be balanced with a tensile force as well
oh well

[pinchies]

Thanks Mao! =D (I don't think I got *any* wrong!) I 'll just need to see the multi though... that dodgy capacitor one...

[Mao]

Thanks Mao! =D (I don't think I got *any* wrong!) I 'll just need to see the multi though... that dodgy capacitor one...

well done!

[dcc: $10 on this guy duxing physics]

[zzdfa]

Captain, (or anyone else who has the exam paper), Q12 Further electronics, was it asking for power dissapation over the 10kO resistor or the 10O resistor? Was there even a 10kO resistor in the circuit?

[chid]

This bridge question,

what were the two questions asked on the exam (in order) again (and was choice A tension for both questions)

Thanks, I'm just a little forgetful/confused

[4xrp]

Is there anywhere we can get a copy of the exam online? Or is anyone who has it able to put it up?

[jay.]

Is there anywhere we can get a copy of the exam online? Or is anyone who has it able to put it up?

that would be mighty helpful..

[costargh]

Don't you guys take your exam papers with you? We are told to take EVERYTHING with us (except obviously the answer book)

[iamdan08]

There is only one booklet. Question and answer in one.

[Mao]

Don't you guys take your exam papers with you? We are told to take EVERYTHING with us (except obviously the answer book)

we answer in the question booklet in science subjects. [just like math]

[Mao]

Captain, (or anyone else who has the exam paper), Q12 Further electronics, was it asking for power dissapation over the 10kO resistor or the 10O resistor? Was there even a 10kO resistor in the circuit?

it was the 10 ohms resistor